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  <title>CSS Box Sizing Module Level 3</title>
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 <body class="h-entry">
  <div class="head">
   <p data-fill-with="logo"><a class="logo" href="https://www.w3.org/"> <img alt="W3C" height="48" src="https://www.w3.org/StyleSheets/TR/2016/logos/W3C" width="72"> </a> </p>
   <h1 class="p-name no-ref" id="title">CSS Box Sizing Module Level 3</h1>
   <h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="content">Editor’s Draft, <time class="dt-updated" datetime="1970-01-01">1 January 1970</time></span></h2>
   <details>
    <summary>Specification Metadata</summary>
    <div data-fill-with="spec-metadata">
     <dl>
      <dt>This version:
      <dd><a class="u-url" href="https://drafts.csswg.org/css-sizing-3/">https://drafts.csswg.org/css-sizing-3/</a>
      <dt>Latest published version:
      <dd><a href="https://www.w3.org/TR/css-sizing-3/">https://www.w3.org/TR/css-sizing-3/</a>
      <dt>Previous Versions:
      <dd><a href="https://www.w3.org/TR/2019/WD-css-sizing-3-20190522/" rel="prev">https://www.w3.org/TR/2019/WD-css-sizing-3-20190522/</a>
      <dd><a href="https://www.w3.org/TR/2018/WD-css-sizing-3-20180304/" rel="prev">https://www.w3.org/TR/2018/WD-css-sizing-3-20180304/</a>
      <dd><a href="https://www.w3.org/TR/2017/WD-css-sizing-3-20170207/" rel="prev">https://www.w3.org/TR/2017/WD-css-sizing-3-20170207/</a>
      <dt class="editor">Editors:
      <dd class="editor p-author h-card vcard" data-editor-id="42199"><a class="p-name fn u-url url" href="http://xanthir.com/contact/">Tab Atkins</a> (<span class="p-org org">Google</span>)
      <dd class="editor p-author h-card vcard" data-editor-id="35400"><a class="p-name fn u-url url" href="http://fantasai.inkedblade.net/contact">Elika J. Etemad / fantasai</a> (<span class="p-org org">Invited Expert</span>)
      <dt>Suggest an Edit for this Spec:
      <dd><a href="https://github.com/w3c/csswg-drafts/blob/master/css-sizing-3/Overview.bs">GitHub Editor</a>
      <dt>Issue Tracking:
      <dd><a href="https://github.com/w3c/csswg-drafts/labels/css-sizing-3">GitHub Issues</a>
     </dl>
    </div>
   </details>
   <div data-fill-with="warning"></div>
   <p class="copyright" data-fill-with="copyright"><a href="https://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> © 1970 <a href="https://www.w3.org/"><abbr title="World Wide Web Consortium">W3C</abbr></a><sup>®</sup> (<a href="https://www.csail.mit.edu/"><abbr title="Massachusetts Institute of Technology">MIT</abbr></a>, <a href="https://www.ercim.eu/"><abbr title="European Research Consortium for Informatics and Mathematics">ERCIM</abbr></a>, <a href="https://www.keio.ac.jp/">Keio</a>, <a href="https://ev.buaa.edu.cn/">Beihang</a>). W3C <a href="https://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>, <a href="https://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and <a href="https://www.w3.org/Consortium/Legal/2015/copyright-software-and-document">permissive document license</a> rules apply. </p>
   <hr title="Separator for header">
  </div>
  <div class="p-summary" data-fill-with="abstract">
   <h2 class="no-num no-toc no-ref heading settled" id="abstract"><span class="content">Abstract</span></h2>
   <p>This module extends the CSS sizing properties with keywords that represent content-based "intrinsic" sizes and context-based "extrinsic" sizes, allowing CSS to more easily describe boxes that fit their content or fit into a particular layout context.</p>
    <a href="https://www.w3.org/TR/CSS/">CSS</a> is a language for describing the rendering of structured documents
(such as HTML and XML)
on screen, on paper, etc. 
  </div>
  <h2 class="no-num no-toc no-ref heading settled" id="status"><span class="content">Status of this document</span></h2>
  <div data-fill-with="status">
   <p> This is a public copy of the editors’ draft.
	It is provided for discussion only and may change at any moment.
	Its publication here does not imply endorsement of its contents by W3C.
	Don’t cite this document other than as work in progress. </p>
   <p> <a href="https://github.com/w3c/csswg-drafts/issues">GitHub Issues</a> are preferred for discussion of this specification.
	When filing an issue, please put the text “css-sizing” in the title,
	preferably like this:
	“[css-sizing] <i data-lt>…summary of comment…</i>”.
	All issues and comments are <a href="https://lists.w3.org/Archives/Public/public-css-archive/">archived</a>,
	and there is also a <a href="https://lists.w3.org/Archives/Public/www-style/">historical archive</a>. </p>
   <p> This document was produced by the <a href="https://www.w3.org/Style/CSS/">CSS Working Group</a>. </p>
   <p> This document was produced by a group operating under
	the <a href="https://www.w3.org/Consortium/Patent-Policy/">W3C Patent Policy</a>.
	W3C maintains a <a href="https://www.w3.org/2004/01/pp-impl/32061/status" rel="disclosure">public list of any patent disclosures</a> made in connection with the deliverables of the group;
	that page also includes instructions for disclosing a patent.
	An individual who has actual knowledge of a patent which the individual believes contains <a href="https://www.w3.org/Consortium/Patent-Policy/#def-essential">Essential Claim(s)</a> must disclose the information in accordance with <a href="https://www.w3.org/Consortium/Patent-Policy/#sec-Disclosure">section 6 of the W3C Patent Policy</a>. </p>
   <p> This document is governed by the <a href="https://www.w3.org/2019/Process-20190301/" id="w3c_process_revision">1 March 2019 W3C Process Document</a>. </p>
   <p></p>
  </div>
  <div data-fill-with="at-risk"></div>
  <nav data-fill-with="table-of-contents" id="toc">
   <h2 class="no-num no-toc no-ref" id="contents">Table of Contents</h2>
   <ol class="toc" role="directory">
    <li>
     <a href="#intro"><span class="secno">1</span> <span class="content"> Introduction</span></a>
     <ol class="toc">
      <li><a href="#placement"><span class="secno">1.1</span> <span class="content"> Module interactions</span></a>
      <li><a href="#values"><span class="secno">1.2</span> <span class="content"> Values</span></a>
     </ol>
    <li>
     <a href="#terms"><span class="secno">2</span> <span class="content"> Terminology</span></a>
     <ol class="toc">
      <li><a href="#auto-box-sizes"><span class="secno">2.1</span> <span class="content"> Auto Box Sizes</span></a>
      <li><a href="#contributions"><span class="secno">2.2</span> <span class="content"> Intrinsic Size Contributions</span></a>
      <li><a href="#constraints"><span class="secno">2.3</span> <span class="content"> Intrinsic Size Constraints</span></a>
     </ol>
    <li>
     <a href="#specifying-sizes"><span class="secno">3</span> <span class="content"> Specifying Box Sizes</span></a>
     <ol class="toc">
      <li>
       <a href="#sizing-properties"><span class="secno">3.1</span> <span class="content"> Sizing Properties</span></a>
       <ol class="toc">
        <li><a href="#preferred-size-properties"><span class="secno">3.1.1</span> <span class="content"> Preferred Size Properties: the <span class="property">width</span> and <span class="property">height</span> properties</span></a>
        <li><a href="#min-size-properties"><span class="secno">3.1.2</span> <span class="content"> Minimum Size Properties: the <span class="property">min-width</span> and <span class="property">min-height</span> properties</span></a>
        <li><a href="#max-size-properties"><span class="secno">3.1.3</span> <span class="content"> Maximum Size Properties: the <span class="property">max-width</span> and <span class="property">max-height</span> properties</span></a>
       </ol>
      <li>
       <a href="#sizing-values"><span class="secno">3.2</span> <span class="content"> Sizing Values: the <span class="production">&lt;length-percentage></span>, <span class="css">auto</span> | <span class="css">none</span>, <span class="css">min-content</span>, <span class="css">max-content</span>, and <span class="css">fit-content()</span> values</span></a>
       <ol class="toc">
        <li><a href="#behave-auto"><span class="secno">3.2.1</span> <span class="content"> “Behaving as <span class="css">auto</span>”</span></a>
        <li><a href="#the-contain-floats-value"><span class="secno">3.2.2</span> <span class="content"> Containing or Excluding Floats</span></a>
       </ol>
      <li><a href="#box-sizing"><span class="secno">3.3</span> <span class="content"> Box Edges for Sizing: the <span class="property">box-sizing</span> property</span></a>
      <li><a href="#column-sizing"><span class="secno">3.4</span> <span class="content"> New Column Sizing Values: the <span class="css">min-content</span>, <span class="css">max-content</span>, and <span class="css">fit-content()</span> values</span></a>
     </ol>
    <li>
     <a href="#intrinsic"><span class="secno">4</span> <span class="content"> Intrinsic Size Determination</span></a>
     <ol class="toc">
      <li><a href="#intrinsic-sizes"><span class="secno">4.1</span> <span class="content"> Intrinsic Sizes</span></a>
      <li><a href="#intrinsic-contribution"><span class="secno">4.2</span> <span class="content"> Intrinsic Contributions</span></a>
     </ol>
    <li>
     <a href="#extrinsic"><span class="secno">5</span> <span class="content"> Extrinsic Size Determination</span></a>
     <ol class="toc">
      <li><a href="#percentage-sizing"><span class="secno">5.1</span> <span class="content"> Percentage Sizing</span></a>
     </ol>
    <li><a href="#min-content-zero"><span class="secno"></span> <span class="content"> Compressible Replaced Elements</span></a>
    <li><a href="#changes"><span class="secno"></span> <span class="content"> Changes</span></a>
    <li><a href="#acknowledgments"><span class="secno"></span> <span class="content"> Acknowledgments</span></a>
    <li><a href="#priv-sec"><span class="secno"></span> <span class="content"> Privacy and Security Considerations</span></a>
    <li>
     <a href="#conformance"><span class="secno"></span> <span class="content"> Conformance</span></a>
     <ol class="toc">
      <li><a href="#document-conventions"><span class="secno"></span> <span class="content"> Document conventions</span></a>
      <li><a href="#conform-classes"><span class="secno"></span> <span class="content"> Conformance classes</span></a>
      <li>
       <a href="#conform-responsible"><span class="secno"></span> <span class="content"> Requirements for Responsible Implementation of CSS</span></a>
       <ol class="toc">
        <li><a href="#conform-partial"><span class="secno"></span> <span class="content"> Partial Implementations</span></a>
        <li><a href="#conform-future-proofing"><span class="secno"></span> <span class="content"> Implementations of Unstable and Proprietary Features</span></a>
        <li><a href="#conform-testing"><span class="secno"></span> <span class="content"> Implementations of CR-level Features</span></a>
       </ol>
     </ol>
    <li>
     <a href="#index"><span class="secno"></span> <span class="content">Index</span></a>
     <ol class="toc">
      <li><a href="#index-defined-here"><span class="secno"></span> <span class="content">Terms defined by this specification</span></a>
      <li><a href="#index-defined-elsewhere"><span class="secno"></span> <span class="content">Terms defined by reference</span></a>
     </ol>
    <li>
     <a href="#references"><span class="secno"></span> <span class="content">References</span></a>
     <ol class="toc">
      <li><a href="#normative"><span class="secno"></span> <span class="content">Normative References</span></a>
      <li><a href="#informative"><span class="secno"></span> <span class="content">Informative References</span></a>
     </ol>
    <li><a href="#property-index"><span class="secno"></span> <span class="content">Property Index</span></a>
    <li><a href="#issues-index"><span class="secno"></span> <span class="content">Issues Index</span></a>
   </ol>
  </nav>
  <main>
   <h2 class="heading settled" data-level="1" id="intro"><span class="secno">1. </span><span class="content"> Introduction</span><a class="self-link" href="#intro"></a></h2>
   <p><em>This section is not normative.</em> </p>
   <p> CSS layout has several different concepts of automatic sizing that are used in various layout calculations.
		This section defines some more precise terminology
		to help connect the layout behaviors of this spec to the calculations used in other modules,
		and some new keywords for the <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width">width</a> and <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height">height</a> properties
		to allow authors to assign elements the dimensions resulting from these size calculations. </p>
   <p class="issue" id="issue-664b2cc3"><a class="self-link" href="#issue-664b2cc3"></a> This spec needs illustrations! See <a href="https://github.com/w3c/csswg-drafts/issues/1938">issue</a>.</p>
   <h3 class="heading settled" data-level="1.1" id="placement"><span class="secno">1.1. </span><span class="content"> Module interactions</span><a class="self-link" href="#placement"></a></h3>
   <p>This module extends the <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width①">width</a>, <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height①">height</a>, <a class="property" data-link-type="propdesc" href="#propdef-min-width" id="ref-for-propdef-min-width">min-width</a>, <a class="property" data-link-type="propdesc" href="#propdef-min-height" id="ref-for-propdef-min-height">min-height</a>, <a class="property" data-link-type="propdesc" href="#propdef-max-width" id="ref-for-propdef-max-width">max-width</a>, <a class="property" data-link-type="propdesc" href="#propdef-max-height" id="ref-for-propdef-max-height">max-height</a>, and <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-multicol-1/#propdef-column-width" id="ref-for-propdef-column-width">column-width</a> features defined in <a data-link-type="biblio" href="#biblio-css2">[CSS2]</a> chapter 10 and in <a data-link-type="biblio" href="#biblio-css3col">[CSS3COL]</a> </p>
   <p>The definition of the <a class="property" data-link-type="propdesc" href="#propdef-box-sizing" id="ref-for-propdef-box-sizing">box-sizing</a> property in this module supersedes the one in <a data-link-type="biblio" href="#biblio-css-ui-3">[CSS-UI-3]</a>. </p>
   <h3 class="heading settled" data-level="1.2" id="values"><span class="secno">1.2. </span><span class="content"> Values</span><a class="self-link" href="#values"></a></h3>
   <p>This specification follows the <a href="https://www.w3.org/TR/CSS2/about.html#property-defs">CSS property definition conventions</a> from <a data-link-type="biblio" href="#biblio-css2">[CSS2]</a>.
	Value types not defined in this specification are defined in CSS Values &amp; Units <a data-link-type="biblio" href="#biblio-css-values-3">[CSS-VALUES-3]</a>.
	Other CSS modules may expand the definitions of these value types.</p>
   <p>In addition to the property-specific values listed in their definitions,
	all properties defined in this specification
	also accept the <a data-link-type="dfn" href="https://drafts.csswg.org/css-values-4/#css-wide-keywords" id="ref-for-css-wide-keywords">CSS-wide keywords</a> keywords as their property value.
	For readability they have not been repeated explicitly.</p>
   <h2 class="heading settled" data-level="2" id="terms"><span class="secno">2. </span><span class="content"> Terminology</span><a class="self-link" href="#terms"></a></h2>
   <dl>
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="size">size</dfn> 
    <dd>
      A one- or two-dimensional measurement:
			a <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#block-size" id="ref-for-block-size">block size</a> and/or <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#inline-size" id="ref-for-inline-size">inline size</a>;
			alternatively a width and/or height. 
     <figure>
       <img alt="In left-to-right, top-to-bottom horizontal English,
				          the horizontal width and inline size are synonymous,
				          and vertical height and block size are synonymous." src="images/sizing-ltr-tb.svg" style="max-width: 49%;"> <img alt="In top-to-bottom, right-to-left vertical Japanese,
				           the horizontal width and block size are synonymous,
				           and vertical height and inline size are synonymous." src="images/sizing-ttb-rl.svg" style="max-width: 49%;"> 
      <figcaption>Whether the <a data-link-type="dfn" href="#width" id="ref-for-width">width</a> or <a data-link-type="dfn" href="#height" id="ref-for-height">height</a> corresponds
				to an <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#inline-size" id="ref-for-inline-size①">inline size</a> or <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#block-size" id="ref-for-block-size①">block size</a> depends on the <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#writing-mode" id="ref-for-writing-mode">writing mode</a>.</figcaption>
     </figure>
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="inner-size">inner size</dfn> 
    <dd> The <a href="https://www.w3.org/TR/css2/box.html#box-dimensions">content-box</a> size of a <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#box" id="ref-for-box">box</a>. 
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="outer-size">outer size</dfn> 
    <dd> The <a href="https://www.w3.org/TR/css2/box.html#box-dimensions">margin-box</a> size of a <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#box" id="ref-for-box①">box</a>. 
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="definite|definite size" id="definite">definite size</dfn> 
    <dd>
      A size that can be determined without performing layout;
			that is, a <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#length-value" id="ref-for-length-value" title="Expands to: em | vb | ch | cm | vh | vi | in | ex | vw | ic | pt | px | lh | pc | rem | rlh | vmax | advance measure | vmin | mm | cap | q">&lt;length></a>,
			a measure of text (without consideration of line-wrapping),
			a size of the <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#initial-containing-block" id="ref-for-initial-containing-block">initial containing block</a>,
			or a <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#percentage-value" id="ref-for-percentage-value">&lt;percentage></a> or other formula
			(such the <a href="https://www.w3.org/TR/CSS2/visudet.html#blockwidth">“stretch-fit” sizing of non-replaced blocks</a> <a data-link-type="biblio" href="#biblio-css2">[CSS2]</a>)
			that is resolved solely against <a data-link-type="dfn" href="#definite" id="ref-for-definite">definite</a> sizes. 
     <p>Additionally, the size of the <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#containing-block" id="ref-for-containing-block">containing block</a> of an absolutely positioned element is always <a data-link-type="dfn" href="#definite" id="ref-for-definite①">definite</a> with respect to that element.</p>
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="indefinite|indefinite size" id="indefinite">indefinite size</dfn> 
    <dd> A size that is not <a data-link-type="dfn" href="#definite" id="ref-for-definite②">definite</a>. <a data-link-type="dfn" href="#indefinite" id="ref-for-indefinite">Indefinite</a> <a data-link-type="dfn" href="#available" id="ref-for-available">available space</a> is essentially infinite. 
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-local-lt="available" data-lt="available space|available inline space|available block space" id="available">available space</dfn> 
    <dd> A size representing the space into which a box is laid out,
			as determined by
			the rules of the formatting context in which it participates.
			The space available to a box is usually
			either a measurement of its <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#containing-block" id="ref-for-containing-block①">containing block</a> (if that is <a data-link-type="dfn" href="#definite" id="ref-for-definite③">definite</a>)
			or an infinite size (when it is <a data-link-type="dfn" href="#indefinite" id="ref-for-indefinite①">indefinite</a>). <a data-link-type="dfn" href="#available" id="ref-for-available①">Available space</a> can alternatively be either a <a data-link-type="dfn" href="#min-content-constraint" id="ref-for-min-content-constraint">min-content constraint</a> or
			a <a data-link-type="dfn" href="#max-content-constraint" id="ref-for-max-content-constraint">max-content constraint</a>. 
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="stretch-fit">stretch fit</dfn> 
    <dd>
      The <a data-link-type="dfn" href="#stretch-fit" id="ref-for-stretch-fit">stretch fit</a> into a given size
			is that size,
			minus the element’s computed margins (not collapsed, treating <span class="css">auto</span> as zero),
			border, and padding in the given dimension
			(such that the outer size is a perfect fit),
			and flooring at zero
			(so that the inner size is not negative). 
     <p class="note" role="note"> Note: This is the formula used to calculate the <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto">auto</a> widths
				of non-replaced blocks in normal flow in <a href="https://www.w3.org/TR/CSS2/visudet.html#blockwidth">CSS2.1§10.3.3</a>. </p>
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="fallback|fallback size" id="fallback">fallback size</dfn> 
    <dd> Some sizing algorithms do not work well with an infinite size.
			In these cases, the <a data-link-type="dfn" href="#fallback" id="ref-for-fallback">fallback size</a> is used instead.
			Unless otherwise specified,
			this is the size of the <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#initial-containing-block" id="ref-for-initial-containing-block①">initial containing block</a>. 
   </dl>
   <h3 class="heading settled" data-level="2.1" id="auto-box-sizes"><span class="secno">2.1. </span><span class="content"> Auto Box Sizes</span><a class="self-link" href="#auto-box-sizes"></a></h3>
   <p>There are four types of automatically-determined sizes in CSS
	(sizes resulting from <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto①">auto</a> sizing rules, depending on context):</p>
   <dl>
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="stretch-fit-size">stretch-fit size</dfn> 
    <dt><dfn data-dfn-type="dfn" data-export id="stretch-fit-inline-size">stretch-fit inline size<a class="self-link" href="#stretch-fit-inline-size"></a></dfn> 
    <dt><dfn data-dfn-type="dfn" data-export id="stretch-fit-block-size">stretch-fit block size<a class="self-link" href="#stretch-fit-block-size"></a></dfn> 
    <dd>
      The <a data-link-type="dfn" href="#size" id="ref-for-size">size</a> a box would take
			if its <a data-link-type="dfn" href="#outer-size" id="ref-for-outer-size">outer size</a> filled the <a data-link-type="dfn" href="#available" id="ref-for-available②">available space</a> in the given axis;
			in other words, the <a data-link-type="dfn" href="#stretch-fit" id="ref-for-stretch-fit①">stretch fit</a> into the <span id="ref-for-available③">available space</span>,
			if that is <a data-link-type="dfn" href="#definite" id="ref-for-definite④">definite</a>.
			Undefined if the <span id="ref-for-available④">available space</span> is <a data-link-type="dfn" href="#indefinite" id="ref-for-indefinite②">indefinite</a>. 
     <p class="note" role="note"><span>Note:</span> For the <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#inline-axis" id="ref-for-inline-axis">inline axis</a>, this is called the “available width” in <a href="https://www.w3.org/TR/CSS2/visudet.html#float-width">CSS2.1§10.3.5</a> and computed by the rules in <a href="https://www.w3.org/TR/CSS2/visudet.html#blockwidth">CSS2.1§10.3.3</a>.</p>
     <p class="note" role="note"><span>Note:</span> Calculations involving this size need to specify a fallback behavior
			for when the <a data-link-type="dfn" href="#available" id="ref-for-available⑤">available space</a> is <a data-link-type="dfn" href="#indefinite" id="ref-for-indefinite③">indefinite</a> if that happens to be possible.</p>
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="max-content | max-content size" id="max-content">max-content size</dfn> 
    <dd>
      A box’s “ideal” <a data-link-type="dfn" href="#size" id="ref-for-size①">size</a> in a given axis when given infinite available space.
			Usually this is the smallest <span id="ref-for-size②">size</span> the box could take in that axis
			while still fitting around its contents,
			i.e. minimizing unfilled space while avoiding overflow. 
     <dl>
      <dt data-md><dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="max-content-inline-size">max-content inline size</dfn>
      <dd data-md>
       <p>The box’s “ideal” <a data-link-type="dfn" href="#size" id="ref-for-size③">size</a> in the <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#inline-axis" id="ref-for-inline-axis①">inline axis</a>.
Usually the narrowest <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#inline-size" id="ref-for-inline-size②">inline size</a> it could take while fitting around its contents
if <em>none</em> of the soft wrap opportunities within the box were taken.
(See <a href="#intrinsic">§ 4 Intrinsic Size Determination</a>.)</p>
       <p class="note" role="note"><span>Note:</span> This is called the “preferred width” in <a href="https://www.w3.org/TR/CSS2/visudet.html#float-width">CSS2.1§10.3.5</a> and the “maximum cell width” in <a href="https://www.w3.org/TR/CSS2/tables.html#auto-table-layout">CSS2.1§17.5.2.2</a>.</p>
      <dt data-md><dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="max-content-block-size">max-content block size</dfn>
      <dd data-md>
       <p>The box’s “ideal” <a data-link-type="dfn" href="#size" id="ref-for-size④">size</a> in the <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#block-axis" id="ref-for-block-axis">block axis</a>.
Usually the <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#block-size" id="ref-for-block-size②">block size</a> of the content after layout.</p>
     </dl>
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="min-content | min-content size" id="min-content">min-content size</dfn> 
    <dd>
      The smallest <a data-link-type="dfn" href="#size" id="ref-for-size⑤">size</a> a box could take
			that doesn’t lead to overflow
			that could be avoided by choosing a larger <span id="ref-for-size⑥">size</span>.
			(See <a href="#intrinsic">§ 4 Intrinsic Size Determination</a>.) 
     <dl>
      <dt data-md><dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="min-content-inline-size">min-content inline size</dfn>
      <dd data-md>
       <p>The narrowest <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#inline-size" id="ref-for-inline-size③">inline size</a> a box could take
that doesn’t lead to inline-dimension overflow
that could be avoided by choosing a larger <span id="ref-for-inline-size④">inline size</span>.
Roughly, the <span id="ref-for-inline-size⑤">inline size</span> that would fit around its contents
if <em>all</em> soft wrap opportunities within the box were taken.</p>
       <p class="note" role="note"><span>Note:</span> This is called the “preferred minimum width” in <a href="https://www.w3.org/TR/CSS2/visudet.html#float-width">CSS2.1§10.3.5</a> and the “minimum content width” in <a href="https://www.w3.org/TR/CSS2/tables.html#auto-table-layout">CSS2.1§17.5.2.2</a>.</p>
      <dt data-md><dfn data-dfn-type="dfn" data-export id="min-content-block-size">min-content block size<a class="self-link" href="#min-content-block-size"></a></dfn>
      <dd data-md>
       <p>In general,
and definitely for <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#block-container" id="ref-for-block-container">block containers</a>, tables, and <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#inline-box" id="ref-for-inline-box">inline boxes</a>,
this is equivalent to the <a data-link-type="dfn" href="#max-content-block-size" id="ref-for-max-content-block-size">max-content block size</a>.</p>
     </dl>
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="fit-content-size">fit-content size</dfn> 
    <dt><dfn data-dfn-type="dfn" data-export id="fit-content-inline-size">fit-content inline size<a class="self-link" href="#fit-content-inline-size"></a></dfn> 
    <dt><dfn data-dfn-type="dfn" data-export id="fit-content-block-size">fit-content block size<a class="self-link" href="#fit-content-block-size"></a></dfn> 
    <dd>
      If the <a data-link-type="dfn" href="#available" id="ref-for-available⑥">available space</a> in a given axis is <a data-link-type="dfn" href="#definite" id="ref-for-definite⑤">definite</a>,
			equal to <code>min(<a data-link-type="dfn" href="#max-content" id="ref-for-max-content">max-content size</a>, max(<a data-link-type="dfn" href="#min-content" id="ref-for-min-content">min-content size</a>, <a data-link-type="dfn" href="#stretch-fit-size" id="ref-for-stretch-fit-size">stretch-fit size</a>))</code>.
			Otherwise, equal to the <a data-link-type="dfn" href="#max-content" id="ref-for-max-content①">max-content size</a> in that axis. 
     <p class="note" role="note"><span>Note:</span> This is called the “shrink-to-fit” width in <a href="https://www.w3.org/TR/CSS2/visudet.html#float-width">CSS2.1§10.3.5</a> and <a href="https://www.w3.org/TR/css3-multicol/#pseudo-algorithm">CSS Multi-column Layout § 3.4</a>.</p>
    <dt><dfn data-dfn-type="dfn" data-export id="intrinsic-size">intrinsic size<a class="self-link" href="#intrinsic-size"></a></dfn> 
    <dd> A <a data-link-type="dfn" href="#max-content" id="ref-for-max-content②">max-content size</a> or <a data-link-type="dfn" href="#min-content" id="ref-for-min-content①">min-content size</a>,
			i.e. a size arising primarily from the size of the content.
			(Some uses of this term may refer also to sizes
			derived primarily from one of these two sizes.) 
   </dl>
   <h3 class="heading settled" data-level="2.2" id="contributions"><span class="secno">2.2. </span><span class="content"> Intrinsic Size Contributions</span><a class="self-link" href="#contributions"></a></h3>
   <dl>
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="max-content contribution|max-content inline-size contribution|max-content block-size contribution" id="max-content-contribution">max-content contribution</dfn> 
    <dd> The size that a box contributes to its <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#containing-block" id="ref-for-containing-block②">containing block</a>’s <a data-link-type="dfn" href="#max-content" id="ref-for-max-content③">max-content size</a>. 
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="min-content contribution|min-content inline-size contribution|min-content block-size contribution" id="min-content-contribution">min-content contribution</dfn> 
    <dd> The size that a box contributes to its <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#containing-block" id="ref-for-containing-block③">containing block</a>’s <a data-link-type="dfn" href="#min-content" id="ref-for-min-content②">min-content size</a>. 
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="intrinsic-size-contribution">intrinsic size contribution</dfn> 
    <dd> A <a data-link-type="dfn" href="#max-content-contribution" id="ref-for-max-content-contribution">max-content contribution</a>, <a data-link-type="dfn" href="#min-content-contribution" id="ref-for-min-content-contribution">min-content contribution</a>,
			or similarly-calculated content-based size contribution. 
   </dl>
   <p>Intrinsic size contributions are based on the <a data-link-type="dfn" href="#outer-size" id="ref-for-outer-size①">outer size</a> of the box;
	for this purpose <span class="css">auto</span> margins are treated as zero.</p>
   <h3 class="heading settled" data-dfn-type="dfn" data-export data-level="2.3" data-lt="intrinsic size constraint" id="constraints"><span class="secno">2.3. </span><span class="content"> Intrinsic Size Constraints</span><a class="self-link" href="#constraints"></a></h3>
   <dl>
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="max-content-constraint">max-content constraint</dfn> 
    <dd> A sizing constraint imposed by the box’s <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#containing-block" id="ref-for-containing-block④">containing block</a> that causes it to produce its <a data-link-type="dfn" href="#max-content-contribution" id="ref-for-max-content-contribution①">max-content contribution</a>. 
    <dt><dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="min-content-constraint">min-content constraint</dfn> 
    <dd> A sizing constraint imposed by the box’s <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#containing-block" id="ref-for-containing-block⑤">containing block</a> that causes it to produce its <a data-link-type="dfn" href="#min-content-contribution" id="ref-for-min-content-contribution①">min-content contribution</a>. 
   </dl>
   <h2 class="heading settled" data-level="3" id="specifying-sizes"><span class="secno">3. </span><span class="content"> Specifying Box Sizes</span><span id="size-keywords"></span><a class="self-link" href="#specifying-sizes"></a></h2>
   <h3 class="heading settled" data-level="3.1" id="sizing-properties"><span class="secno">3.1. </span><span class="content"> Sizing Properties</span><a class="self-link" href="#sizing-properties"></a></h3>
   <p>This section defines the <dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="sizing property" id="sizing-property">sizing properties</dfn> <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width②">width</a>, <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height②">height</a>, <a class="property" data-link-type="propdesc" href="#propdef-min-width" id="ref-for-propdef-min-width①">min-width</a>, <a class="property" data-link-type="propdesc" href="#propdef-min-height" id="ref-for-propdef-min-height①">min-height</a>, <a class="property" data-link-type="propdesc" href="#propdef-max-width" id="ref-for-propdef-max-width①">max-width</a>, and <a class="property" data-link-type="propdesc" href="#propdef-max-height" id="ref-for-propdef-max-height①">max-height</a>.
	Their potential values are defined in the next section, <a href="#sizing-values">§ 3.2 Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>.</p>
   <p class="note" role="note"><span>Note:</span> Additional <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#flow-relative" id="ref-for-flow-relative">flow-relative</a> aliases to these properties are defined in <a data-link-type="biblio" href="#biblio-css-logical-1">[CSS-LOGICAL-1]</a>.</p>
   <p class="issue" id="issue-6eb2c542"><a class="self-link" href="#issue-6eb2c542"></a> We would like to define shorthands for each pair of sizing properties
	(e.g. <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width③">width</a> and <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height③">height</a>)
	but there is a naming conflict with the <a class="css" data-link-type="maybe" href="https://drafts.csswg.org/css-page-3/#at-ruledef-page" id="ref-for-at-ruledef-page">@page</a> <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-page-3/#descdef-page-size" id="ref-for-descdef-page-size">size</a> descriptor <a data-link-type="biblio" href="#biblio-css-page-3">[CSS-PAGE-3]</a>,
	so this has been deferred to Level 4.
	Suggestions on how to resolve this problem are welcome,
	see <a href="https://github.com/w3c/csswg-drafts/issues/820">discussion</a>.</p>
   <h4 class="heading settled dfn-paneled" data-dfn-type="dfn" data-export data-level="3.1.1" data-lt="preferred size property" id="preferred-size-properties"><span class="secno">3.1.1. </span><span class="content"> Preferred Size Properties: the <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width④">width</a> and <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height④">height</a> properties</span></h4>
   <table class="def propdef" data-link-for-hint="width">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-width">width</dfn>, <dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-height">height</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod">auto <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one">|</a> <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage">&lt;length-percentage></a> <span id="ref-for-comb-one①">|</span> min-content <span id="ref-for-comb-one②">|</span> max-content <span id="ref-for-comb-one③">|</span> <span style=";white-space:nowrap">fit-content(<a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage①">&lt;length-percentage></a>)</span> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>auto 
     <tr>
      <th>Applies to:
      <td>all elements except <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#non-replaced" id="ref-for-non-replaced">non-replaced</a> <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#inline" id="ref-for-inline">inlines</a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no 
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>relative to width/height of <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#containing-block" id="ref-for-containing-block⑥">containing block</a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>as specified, with <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage②">&lt;length-percentage></a> values computed 
     <tr>
      <th>Canonical order:
      <td>per grammar 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>by computed value type, recursing into <a class="css" data-link-type="maybe" href="#valdef-width-fit-content-length-percentage" id="ref-for-valdef-width-fit-content-length-percentage">fit-content()</a> 
   </table>
   <p>The <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width⑤">width</a> and <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height⑤">height</a> properties specify
	the <dfn data-dfn-type="dfn" data-export data-lt="preferred size" id="preferred-size">preferred<a class="self-link" href="#preferred-size"></a></dfn> (<a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#physical" id="ref-for-physical">physical</a>) <dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="width | preferred width" id="width">width</dfn> and <dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="height | preferred height" id="height">height</dfn> of the box, respectively.</p>
   <h4 class="heading settled dfn-paneled" data-dfn-type="dfn" data-export data-level="3.1.2" data-lt="min size property" id="min-size-properties"><span class="secno">3.1.2. </span><span class="content"> Minimum Size Properties: the <a class="property" data-link-type="propdesc" href="#propdef-min-width" id="ref-for-propdef-min-width②">min-width</a> and <a class="property" data-link-type="propdesc" href="#propdef-min-height" id="ref-for-propdef-min-height②">min-height</a> properties</span></h4>
   <table class="def propdef" data-link-for-hint="min-width">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-min-width">min-width</dfn>, <dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-min-height">min-height</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod">auto <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one④">|</a> <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage③">&lt;length-percentage></a> <span id="ref-for-comb-one⑤">|</span> min-content <span id="ref-for-comb-one⑥">|</span> max-content <span id="ref-for-comb-one⑦">|</span> <span style=";white-space:nowrap">fit-content(<a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage④">&lt;length-percentage></a>)</span> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>auto 
     <tr>
      <th>Applies to:
      <td>all elements that accept <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width⑥">width</a> or <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height⑥">height</a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no 
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>relative to width/height of <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#containing-block" id="ref-for-containing-block⑦">containing block</a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>as specified, with <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage⑤">&lt;length-percentage></a> values computed 
     <tr>
      <th>Canonical order:
      <td>per grammar 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animatable:</a>
      <td>by computed value, recursing into <a class="css" data-link-type="maybe" href="#valdef-width-fit-content-length-percentage" id="ref-for-valdef-width-fit-content-length-percentage①">fit-content()</a> 
   </table>
   <p>The <a class="property" data-link-type="propdesc" href="#propdef-min-width" id="ref-for-propdef-min-width③">min-width</a> and <a class="property" data-link-type="propdesc" href="#propdef-min-height" id="ref-for-propdef-min-height③">min-height</a> properties specify
	the <dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="min width | minimum width | min size | minimum size" id="min-width">minimum width</dfn> (or “min width”)
	and <dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="min height | minimum height" id="min-height">minimum height</dfn> (or “min height”)
	of the box, respectively.</p>
   <p class="note" role="note"><span>Note:</span> The initial value of <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto②">auto</a> is new;
	in <a data-link-type="biblio" href="#biblio-css2">[CSS2]</a> the initial value was zero.</p>
   <h4 class="heading settled dfn-paneled" data-dfn-type="dfn" data-export data-level="3.1.3" data-lt="max size property" id="max-size-properties"><span class="secno">3.1.3. </span><span class="content"> Maximum Size Properties: the <a class="property" data-link-type="propdesc" href="#propdef-max-width" id="ref-for-propdef-max-width②">max-width</a> and <a class="property" data-link-type="propdesc" href="#propdef-max-height" id="ref-for-propdef-max-height②">max-height</a> properties</span></h4>
   <table class="def propdef" data-link-for-hint="max-width">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-max-width">max-width</dfn>, <dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-max-height">max-height</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod">none <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one⑧">|</a> <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage⑥">&lt;length-percentage></a> <span id="ref-for-comb-one⑨">|</span> min-content <span id="ref-for-comb-one①⓪">|</span> max-content <span id="ref-for-comb-one①①">|</span> <span style=";white-space:nowrap">fit-content(<a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage⑦">&lt;length-percentage></a>)</span> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>none 
     <tr>
      <th>Applies to:
      <td>all elements that accept <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width⑦">width</a> or <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height⑦">height</a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no 
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>relative to width/height of <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#containing-block" id="ref-for-containing-block⑧">containing block</a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>as specified, with <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage⑧">&lt;length-percentage></a> values computed 
     <tr>
      <th>Canonical order:
      <td>per grammar 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animatable:</a>
      <td>by computed value, recursing into <a class="css" data-link-type="maybe" href="#valdef-width-fit-content-length-percentage" id="ref-for-valdef-width-fit-content-length-percentage②">fit-content()</a> 
   </table>
   <p>The <a class="property" data-link-type="propdesc" href="#propdef-max-width" id="ref-for-propdef-max-width③">max-width</a> and <a class="property" data-link-type="propdesc" href="#propdef-max-height" id="ref-for-propdef-max-height③">max-height</a> properties specify
	the <dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="max width | maximum width | max size | maximum size" id="max-width">maximum width</dfn> (or “max width”)
	and <dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="max height | maximum height" id="max-height">maximum height</dfn> (or “max height”)
	of the box, respectively.</p>
   <h3 class="heading settled" data-level="3.2" id="sizing-values"><span class="secno">3.2. </span><span class="content"> Sizing Values: the <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage⑨">&lt;length-percentage></a>, <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto③">auto</a> | <a class="css" data-link-type="maybe" href="#valdef-max-width-none" id="ref-for-valdef-max-width-none">none</a>, <a class="css" data-link-type="maybe" href="#valdef-width-min-content" id="ref-for-valdef-width-min-content">min-content</a>, <a class="css" data-link-type="maybe" href="#valdef-width-max-content" id="ref-for-valdef-width-max-content">max-content</a>, and <a class="css" data-link-type="maybe" href="#valdef-width-fit-content-length-percentage" id="ref-for-valdef-width-fit-content-length-percentage③">fit-content()</a> values</span><span id="width-height-keywords"></span><a class="self-link" href="#sizing-values"></a></h3>
   <dl>
    <dt><dfn class="css" data-dfn-for="width, min-width, max-width, height, min-height, max-height" data-dfn-type="value" data-export id="valdef-width-length-percentage"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage①⓪">&lt;length-percentage></a><a class="self-link" href="#valdef-width-length-percentage"></a></dfn> 
    <dd>
      Specifies the size of the box using <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#length-value" id="ref-for-length-value①" title="Expands to: em | vb | ch | cm | vh | vi | in | ex | vw | ic | pt | px | lh | pc | rem | rlh | vmax | advance measure | vmin | mm | cap | q">&lt;length></a> and/or <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#percentage-value" id="ref-for-percentage-value①">&lt;percentage></a>.
			The <a class="property" data-link-type="propdesc" href="#propdef-box-sizing" id="ref-for-propdef-box-sizing①">box-sizing</a> property indicates whether the <a data-link-type="dfn" href="https://drafts.csswg.org/css-box-3/#content-box" id="ref-for-content-box">content box</a> or <a data-link-type="dfn" href="https://drafts.csswg.org/css-box-3/#border-box" id="ref-for-border-box">border box</a> is measured. 
     <p>Percentages are resolved against the width/height, as appropriate,
			of the box’s <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#containing-block" id="ref-for-containing-block⑨">containing block</a>.
			If, in a particular axis,
			the <span id="ref-for-containing-block①⓪">containing block’s</span> size depends on the box’s size,
			see the relevant layout module
			for special rules on how to resolve percentages.</p>
     <p>Negative values are invalid.</p>
    <dt><dfn class="dfn-paneled css" data-dfn-for="width, height, min-width, min-height" data-dfn-type="value" data-export id="valdef-width-auto">auto</dfn> 
    <dd>
      For <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width⑧">width</a>/<a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height⑧">height</a>, specifies an <dfn class="dfn-paneled" data-dfn-for data-dfn-type="dfn" data-export id="automatic-size">automatic size</dfn>.
			See the relevant layout module for how to calculate this. 
     <p>For <a class="property" data-link-type="propdesc" href="#propdef-min-width" id="ref-for-propdef-min-width④">min-width</a>/<a class="property" data-link-type="propdesc" href="#propdef-min-height" id="ref-for-propdef-min-height④">min-height</a>,
			specifies an <dfn class="dfn-paneled" data-dfn-for data-dfn-type="dfn" data-export id="automatic-minimum-size">automatic minimum size</dfn>.
			Unless otherwise defined by the relevant layout module,
			however,
			it resolves to a used value of <span class="css">0</span>.
			For backwards-compatibility,
			the <a data-link-type="dfn" href="https://drafts.csswg.org/cssom-1/#resolved-value" id="ref-for-resolved-value">resolved value</a> of this keyword is zero
			for boxes of all <a data-link-type="biblio" href="#biblio-css2">[CSS2]</a> <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#display-type" id="ref-for-display-type">display types</a>:
			block and inline boxes,
			inline blocks,
			and all the table layout boxes.
			It also resolves to zero
			when no box is generated.</p>
    <dt><dfn class="dfn-paneled css" data-dfn-for="max-width, max-height" data-dfn-type="value" data-export id="valdef-max-width-none">none</dfn> 
    <dd> No limit on the size of the box. 
    <dt><dfn class="dfn-paneled css" data-dfn-for="width, min-width, max-width, height, min-height, max-height" data-dfn-type="value" data-export id="valdef-width-min-content">min-content</dfn> 
    <dd> Use the <a data-link-type="dfn" href="#min-content" id="ref-for-min-content③">min-content size</a> in the relevant axis;
			for a box’s <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#block-size" id="ref-for-block-size③">block size</a>,
			unless otherwise specified,
			this is equivalent to its <a data-link-type="dfn" href="#automatic-size" id="ref-for-automatic-size">automatic size</a>. 
    <dt><dfn class="dfn-paneled css" data-dfn-for="width, min-width, max-width, height, min-height, max-height" data-dfn-type="value" data-export id="valdef-width-max-content">max-content</dfn> 
    <dd> Use the <a data-link-type="dfn" href="#min-content" id="ref-for-min-content④">min-content size</a> in the relevant axis;
			for a box’s <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#block-size" id="ref-for-block-size④">block size</a>,
			unless otherwise specified,
			this is equivalent to its <a data-link-type="dfn" href="#automatic-size" id="ref-for-automatic-size①">automatic size</a>. 
    <dt><dfn class="dfn-paneled css" data-dfn-for="width, min-width, max-width, height, min-height, max-height" data-dfn-type="value" data-export id="valdef-width-fit-content-length-percentage">fit-content(<a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage①①">&lt;length-percentage></a>)</dfn> 
    <dd>
      Use the fit-content formula
			with the <a data-link-type="dfn" href="#available" id="ref-for-available⑦">available space</a> replaced by the specified argument,
			i.e. <code>min(<a class="css" data-link-type="maybe" href="#valdef-width-max-content" id="ref-for-valdef-width-max-content①">max-content</a>, max(<a class="css" data-link-type="maybe" href="#valdef-width-min-content" id="ref-for-valdef-width-min-content①">min-content</a>, <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage①②">&lt;length-percentage></a>))</code>. 
     <p>For <a data-link-type="dfn" href="#intrinsic-size-contribution" id="ref-for-intrinsic-size-contribution">intrinsic size contributions</a>,
			''fit-content(<a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#length-value" id="ref-for-length-value②" title="Expands to: em | vb | ch | cm | vh | vi | in | ex | vw | ic | pt | px | lh | pc | rem | rlh | vmax | advance measure | vmin | mm | cap | q">&lt;length></a>)'' behaves as the resulting length; <a class="css" data-link-type="maybe" href="#valdef-width-fit-content-length-percentage" id="ref-for-valdef-width-fit-content-length-percentage④">fit-content()</a> containing a <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#percentage-value" id="ref-for-percentage-value②">&lt;percentage></a> behaves
			as <a class="css" data-link-type="maybe" href="#valdef-width-min-content" id="ref-for-valdef-width-min-content②">min-content</a> for <a data-link-type="dfn" href="#min-content-contribution" id="ref-for-min-content-contribution②">min-content contributions</a>,
			and as <a class="css" data-link-type="maybe" href="#valdef-width-max-content" id="ref-for-valdef-width-max-content②">max-content</a> for <a data-link-type="dfn" href="#max-content-contribution" id="ref-for-max-content-contribution②">max-content contributions</a>.</p>
     <p>Negative values are invalid.</p>
   </dl>
   <p>In all cases,
	the used value is floored to preserve a non-negative <a data-link-type="dfn" href="#inner-size" id="ref-for-inner-size">inner size</a>.</p>
   <p class="note" role="note"><span>Note:</span> The <a class="css" data-link-type="maybe" href="#valdef-width-min-content" id="ref-for-valdef-width-min-content③">min-content</a>, <a class="css" data-link-type="maybe" href="#valdef-width-max-content" id="ref-for-valdef-width-max-content③">max-content</a>, and <a class="css" data-link-type="maybe" href="#valdef-width-fit-content-length-percentage" id="ref-for-valdef-width-fit-content-length-percentage⑤">fit-content()</a> values
	are new in Level 3.</p>
   <p class="note" role="note"><span>Note:</span> The <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-flexbox-1/#propdef-flex-basis" id="ref-for-propdef-flex-basis">flex-basis</a> property hereby also gains these new keywords,
	as its values are defined by reference to &lt;<a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width⑨">width</a>>.</p>
   <p class="note" role="note"><span>Note:</span> This section previously defined <span class="css">stretch</span> and <span class="css">fit-content</span> as keywords representing the <a data-link-type="dfn" href="#stretch-fit-size" id="ref-for-stretch-fit-size①">stretch-fit size</a> and <a data-link-type="dfn" href="#fit-content-size" id="ref-for-fit-content-size">fit-content size</a>,
	respectively.
	These keywords have been deferred to Level 4
	(along with an additional <span class="css">contain</span> keyword that
	behaves similarly to <span class="css">stretch</span> but preserves the intrinsic aspect ratio, if any)
	to better work out the implications in situations with <a data-link-type="dfn" href="#indefinite" id="ref-for-indefinite④">indefinite</a> <a data-link-type="dfn" href="#available" id="ref-for-available⑧">available space</a>.</p>
   <h4 class="heading settled" data-level="3.2.1" id="behave-auto"><span class="secno">3.2.1. </span><span class="content"> “Behaving as <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto④">auto</a>”</span><a class="self-link" href="#behave-auto"></a></h4>
   <p>To have a common term for both when <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width①⓪">width</a>/<a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height⑨">height</a> computes to <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto⑤">auto</a> and when it is defined to behave as if <span class="css" id="ref-for-valdef-width-auto⑥">auto</span> were specified
	(as in the case of <a href="https://www.w3.org/TR/CSS2/visudet.html#the-height-property">block percentage heights</a> resolving against an <a data-link-type="dfn" href="#indefinite" id="ref-for-indefinite⑤">indefinite</a> size,
	see <a href="https://www.w3.org/TR/CSS2/visudet.html#the-height-property">CSS2§10.5</a>),
	the property is said to <dfn class="dfn-paneled" data-dfn-type="dfn" data-export data-lt="behave as auto|behaves as auto|behaving as auto" id="behave-as-auto">behave as auto</dfn> in both of these cases.</p>
   <p class="note" role="note"><span>Note:</span> Legacy spec prose defining layout behavior
	might explicitly refer to <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width①①">width</a>/<a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height①⓪">height</a> having a computed value of <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto⑦">auto</a> as a condition;
	these should be interpreted as meaning <a data-link-type="dfn" href="#behave-as-auto" id="ref-for-behave-as-auto">behaves as auto</a>,
	and reported to the CSSWG for updating.</p>
   <p class="issue" id="issue-6215c343"><a class="self-link" href="#issue-6215c343"></a> Replace this section with references to the new term <a data-link-type="dfn" href="#automatic-size" id="ref-for-automatic-size②">automatic size</a>.</p>
   <h4 class="heading settled" data-level="3.2.2" id="the-contain-floats-value"><span class="secno">3.2.2. </span><span class="content"> Containing or Excluding Floats</span><a class="self-link" href="#the-contain-floats-value"></a></h4>
   <p><em>This section is non-normative.</em></p>
   <p>Although <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#block-box" id="ref-for-block-box">block box</a> boundaries are typically pervious to floats,
	sometimes an author needs them to contain their own (descendant) floats
	or to exclude floats from outside.
	For Block layout,
	specifying <a class="css" data-link-type="propdesc" href="https://drafts.csswg.org/css-display-3/#propdef-display" id="ref-for-propdef-display">display: flow-root</a> will make the box a <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#formatting-context" id="ref-for-formatting-context">formatting context</a> root,
	which has this behavior.</p>
   <p class="note" role="note"><span>Note:</span> Boxes participating in Flex, Grid, or Table layout will automatically have this behavior.</p>
   <h3 class="heading settled caniuse-paneled" data-level="3.3" id="box-sizing"><span class="secno">3.3. </span><span class="content"> Box Edges for Sizing: the <a class="property" data-link-type="propdesc" href="#propdef-box-sizing" id="ref-for-propdef-box-sizing②">box-sizing</a> property</span><a class="self-link" href="#box-sizing"></a></h3>
   <table class="def propdef" data-link-for-hint="box-sizing">
    <tbody>
     <tr>
      <th>Name:
      <td><dfn class="dfn-paneled css" data-dfn-type="property" data-export id="propdef-box-sizing">box-sizing</dfn>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">Value:</a>
      <td class="prod">content-box <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one①②">|</a> border-box 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#initial-values">Initial:</a>
      <td>content-box 
     <tr>
      <th>Applies to:
      <td>all elements that accept <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width①②">width</a> or <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height①①">height</a> 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#inherited-property">Inherited:</a>
      <td>no 
     <tr>
      <th><a href="https://drafts.csswg.org/css-values/#percentages">Percentages:</a>
      <td>N/A 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>specified keyword 
     <tr>
      <th>Canonical order:
      <td>per grammar 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>discrete 
   </table>
   <p>The <a class="property" data-link-type="propdesc" href="#propdef-box-sizing" id="ref-for-propdef-box-sizing③">box-sizing</a> property defines whether
	fixed sizes (such as <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#length-value" id="ref-for-length-value③" title="Expands to: em | vb | ch | cm | vh | vi | in | ex | vw | ic | pt | px | lh | pc | rem | rlh | vmax | advance measure | vmin | mm | cap | q">&lt;length></a>s and <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#percentage-value" id="ref-for-percentage-value③">&lt;percentage></a>s)
	are assigned to the <a data-link-type="dfn" href="https://drafts.csswg.org/css-box-3/#content-box" id="ref-for-content-box①">content box</a> or to the <a data-link-type="dfn" href="https://drafts.csswg.org/css-box-3/#border-box" id="ref-for-border-box①">border box</a>.
	It affects the interpretation of all <a data-link-type="dfn" href="#sizing-property" id="ref-for-sizing-property">sizing properties</a>,
	including <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-flexbox-1/#propdef-flex-basis" id="ref-for-propdef-flex-basis①">flex-basis</a>.</p>
   <p>Values have the following meanings:</p>
   <dl>
    <dt><dfn class="css" data-dfn-for="box-sizing" data-dfn-type="value" data-export id="valdef-box-sizing-content-box">content-box<a class="self-link" href="#valdef-box-sizing-content-box"></a></dfn> 
    <dd>
      Sizes specified on <a data-link-type="dfn" href="#sizing-property" id="ref-for-sizing-property①">sizing properties</a> as <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage①③">&lt;length-percentage></a> represent the box’s <a data-link-type="dfn" href="#inner-size" id="ref-for-inner-size①">inner sizes</a>,
			excluding the margins/border/padding:
			they are applied to the <a data-link-type="dfn" href="https://drafts.csswg.org/css-box-3/#content-box" id="ref-for-content-box②">content box</a>.
			The padding and border of the box
			are laid out and drawn <em>outside</em> the specified <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width①③">width</a> and <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height①②">height</a>. 
     <p class="note" role="note"><span>Note:</span> This is the behavior of width and height as specified by CSS2.1,
			and is thus the default.</p>
    <dt><dfn class="dfn-paneled css" data-dfn-for="box-sizing" data-dfn-type="value" data-export id="valdef-box-sizing-border-box">border-box</dfn> 
    <dd>
      Sizes specified on <a data-link-type="dfn" href="#sizing-property" id="ref-for-sizing-property②">sizing properties</a> as <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage①④">&lt;length-percentage></a> represent the box’s visually-apparent sizes,
			including the borders/padding (but not margin):
			they are applied to the <a data-link-type="dfn" href="https://drafts.csswg.org/css-box-3/#border-box" id="ref-for-border-box②">border box</a>.
			The padding and border of the box
			are laid out and drawn <em>inside</em> the specified <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width①④">width</a> and <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height①③">height</a>,
			with the <a data-link-type="dfn" href="https://drafts.csswg.org/css-box-3/#content-box" id="ref-for-content-box③">content box</a> sized to fill the remaining space,
			floored at zero. 
     <p>The content width and height are calculated
			by subtracting the border and padding widths of the respective sides
			from the specified <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage①⑤">&lt;length-percentage></a>.
			As the content width and height <a href="#sizing-values">cannot be negative</a>,
			this computation is floored at zero.</p>
     <p>Used values, as exposed for instance through <code class="idl"><a data-link-type="idl" href="https://drafts.csswg.org/cssom-1/#dom-window-getcomputedstyle" id="ref-for-dom-window-getcomputedstyle">getComputedStyle()</a></code>,
			also refer to the border box.</p>
   </dl>
   <p>Values affected by <a class="property" data-link-type="propdesc" href="#propdef-box-sizing" id="ref-for-propdef-box-sizing④">box-sizing</a> include
	both raw <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage①⑥">&lt;length-percentage></a> values
	and those used in functional notations such as <a class="css" data-link-type="maybe" href="#valdef-width-fit-content-length-percentage" id="ref-for-valdef-width-fit-content-length-percentage⑥">fit-content()</a>.
	In contrast,
	non-quantitative values such as <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto⑧">auto</a> and <a class="css" data-link-type="maybe" href="#valdef-width-min-content" id="ref-for-valdef-width-min-content④">min-content</a> are not influenced by the <span class="property" id="ref-for-propdef-box-sizing⑤">box-sizing</span> property
	(unless otherwise specified).</p>
   <div class="example" id="example-8af7a68e">
    <a class="self-link" href="#example-8af7a68e"></a> For example, the following properties set
		the content-box size of the box to <span class="css">100px</span>,
		with the border-box size calculating to <span class="css">120px</span>: 
<pre class="lang-css highlight"><c- f>.box </c-><c- p>{</c->
  <c- k>box-sizing</c-><c- p>:</c->   content-box<c- p>;</c-> <c- c>/* default */</c->
  <c- k>width</c-><c- p>:</c->        <c- m>100</c-><c- l>px</c-><c- p>;</c->
  <c- k>padding-left</c-><c- p>:</c-> <c- m>10</c-><c- l>px</c-><c- p>;</c->
  <c- k>border-left</c-><c- p>:</c->  <c- m>10</c-><c- l>px</c-> solid<c- p>;</c->
<c- p>}</c->
</pre>
    <p>On the other hand, by changing to <a class="css" data-link-type="maybe" href="#valdef-box-sizing-border-box" id="ref-for-valdef-box-sizing-border-box">border-box</a>,
		the border-box is set to <span class="css">100px</span>,
		with the content-box size calculating to <span class="css">80px</span>:</p>
<pre class="lang-css highlight"><c- f>.box </c-><c- p>{</c->
  <c- k>box-sizing</c-><c- p>:</c->   border-box<c- p>;</c->
  <c- k>width</c-><c- p>:</c->        <c- m>100</c-><c- l>px</c-><c- p>;</c->
  <c- k>padding-left</c-><c- p>:</c-> <c- m>10</c-><c- l>px</c-><c- p>;</c->
  <c- k>border-left</c-><c- p>:</c->  <c- m>10</c-><c- l>px</c-> solid<c- p>;</c->
<c- p>}</c->
</pre>
    <p>The <a data-link-type="dfn" href="#inner-size" id="ref-for-inner-size②">inner size</a> can’t be less than zero,
		so if the <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-box-3/#propdef-padding" id="ref-for-propdef-padding">padding</a> + <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-backgrounds-3/#propdef-border" id="ref-for-propdef-border">border</a> is greater than the specified border-box size,
		the box will end up larger than specified.
		In this case, the content-box size will floor at <span class="css">0px</span> so the border-box size ends up at <span class="css">120px</span>,
		even though <a class="css" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width①⑤">width: 100px</a> is specified for the border box:</p>
<pre class="lang-css highlight"><c- f>.box </c-><c- p>{</c->
  <c- k>box-sizing</c-><c- p>:</c->   border-box<c- p>;</c->
  <c- k>width</c-><c- p>:</c->        <c- m>100</c-><c- l>px</c-><c- p>;</c->
  <c- k>padding-left</c-><c- p>:</c-> <c- m>60</c-><c- l>px</c-><c- p>;</c->
  <c- k>border-left</c-><c- p>:</c->  <c- m>60</c-><c- l>px</c-> solid<c- p>;</c->
  <c- c>/* padding + border = 120px */</c->
<c- p>}</c->
</pre>
   </div>
   <div class="example" id="example-0700ac27">
    <a class="self-link" href="#example-0700ac27"></a> This example uses box-sizing to evenly horizontally split
		two divs with fixed size borders inside a div container,
		which would otherwise require additional markup. 
    <p>sample CSS:</p>
<pre><code class="lang-css highlight"><c- f>div.container </c-><c- p>{</c->
  <c- k>width</c-><c- p>:</c-><c- m>38</c-><c- l>em</c-><c- p>;</c->
  <c- k>border</c-><c- p>:</c-><c- m>1</c-><c- l>em</c-> solid black<c- p>;</c->
<c- p>}</c->

<c- f>div.split </c-><c- p>{</c->
  <c- k>box-sizing</c-><c- p>:</c->border-box<c- p>;</c->
  <c- k>width</c-><c- p>:</c-><c- m>50</c-><c- l>%</c-><c- p>;</c->
  <c- k>border</c-><c- p>:</c-><c- m>1</c-><c- l>em</c-> silver ridge<c- p>;</c->
  <c- k>float</c-><c- p>:</c->left<c- p>;</c->
<c- p>}</c->
</code></pre>
    <p>sample HTML fragment:</p>
<pre><code class="lang-markup highlight"><c- p>&lt;</c-><c- f>div</c-> <c- e>class</c-><c- o>=</c-><c- s>"container"</c-><c- p>></c->
<c- p>&lt;</c-><c- f>div</c-> <c- e>class</c-><c- o>=</c-><c- s>"split"</c-><c- p>></c->This div occupies the left half.<c- p>&lt;/</c-><c- f>div</c-><c- p>></c->
<c- p>&lt;</c-><c- f>div</c-> <c- e>class</c-><c- o>=</c-><c- s>"split"</c-><c- p>></c->This div occupies the right half.<c- p>&lt;/</c-><c- f>div</c-><c- p>></c->
<c- p>&lt;/</c-><c- f>div</c-><c- p>></c->
</code></pre>
    <p>demonstration of sample CSS and HTML:</p>
    <div style="max-width:38em; border:1em solid black">
     <div style="box-sizing:border-box; width:50%; border:1em silver ridge; float:left">This div should occupy the left half.</div>
     <div style="box-sizing:border-box; width:50%; border:1em silver ridge; float:left">This div should occupy the right half.</div>
     The two divs above should appear side by side, each (including borders) 50% of the content width of their container. If instead they are stacked one on top of the other then your browser does not support <a class="property" data-link-type="propdesc" href="#propdef-box-sizing" id="ref-for-propdef-box-sizing⑥">box-sizing</a>.
    </div>
   </div>
   <p class="note" role="note"><span>Note:</span> Certain HTML elements,
	such as <code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/form-elements.html#the-button-element" id="ref-for-the-button-element">button</a></code>,
	default to <a class="css" data-link-type="maybe" href="#valdef-box-sizing-border-box" id="ref-for-valdef-box-sizing-border-box①">border-box</a> behavior.
	See HTML for details on which elements have this behavior.</p>
   <p>In legacy CSS specifications,
	the terms <a data-link-type="dfn" href="#width" id="ref-for-width①">width</a>, <a data-link-type="dfn" href="#height" id="ref-for-height①">height</a>, <a data-link-type="dfn" href="#min-width" id="ref-for-min-width">minimum (min) width</a>, <a data-link-type="dfn" href="#min-height" id="ref-for-min-height">minimum (min) height</a>, <a data-link-type="dfn" href="#max-width" id="ref-for-max-width">maximum (max) width</a>, and <a data-link-type="dfn" href="#max-height" id="ref-for-max-height">maximum (max) height</a> generally refer to the <a data-link-type="dfn" href="#inner-size" id="ref-for-inner-size③">inner</a> size
	(<a data-link-type="dfn" href="https://drafts.csswg.org/css-box-3/#content-box" id="ref-for-content-box④">content-box</a> size)
	of a <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#box" id="ref-for-box②">box</a> unless otherwise indicated.</p>
   <p>Refer to <a href="https://www.w3.org/TR/css3-ui/#box-sizing">CSS User Interface 3 §3.1 Changing the Box Model: the box-sizing property</a> for an explicit disambiguation of these terms
	for the <a href="https://www.w3.org/TR/CSS21/visudet.html">Visual formatting model details</a> section of <a data-link-type="biblio" href="#biblio-css2">[CSS2]</a>.</p>
   <div class="advisement">To avoid ambiguities,
	specification authors should avoid ambiguous uses of terms such as width or height without further qualification,
	and should explicitely refer and link to
	the <a data-link-type="dfn" href="#inner-size" id="ref-for-inner-size④">inner</a> size,
	the <a data-link-type="dfn" href="#outer-size" id="ref-for-outer-size②">outer</a> size,
	the size of the <a href="https://www.w3.org/TR/css2/box.html#box-dimensions">border-box</a>,
	the <a data-link-type="dfn" href="https://drafts.csswg.org/css-cascade-4/#computed-value" id="ref-for-computed-value">computed value</a> of the <a data-link-type="dfn" href="#sizing-property" id="ref-for-sizing-property③">sizing properties</a>,
	etc,
	as appropriate for each case. </div>
   <h3 class="heading settled" data-level="3.4" id="column-sizing"><span class="secno">3.4. </span><span class="content"> New Column Sizing Values: the <a class="css" data-link-type="maybe" href="#valdef-column-width-min-content" id="ref-for-valdef-column-width-min-content">min-content</a>, <a class="css" data-link-type="maybe" href="#valdef-column-width-max-content" id="ref-for-valdef-column-width-max-content">max-content</a>, and <a class="css" data-link-type="maybe" href="#valdef-column-width-fit-content-length-percentage" id="ref-for-valdef-column-width-fit-content-length-percentage">fit-content()</a> values</span><a class="self-link" href="#column-sizing"></a></h3>
   <table class="def propdef partial" data-link-for-hint="column-width">
    <tbody>
     <tr>
      <th>Name:
      <td><a class="css" data-link-type="property" href="https://drafts.csswg.org/css-multicol-1/#propdef-column-width" id="ref-for-propdef-column-width①">column-width</a>
     <tr class="value">
      <th><a href="https://drafts.csswg.org/css-values/#value-defs">New values:</a>
      <td class="prod">min-content <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-4/#comb-one" id="ref-for-comb-one①③">|</a> max-content <span id="ref-for-comb-one①④">|</span> fit-content(<a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage①⑦">&lt;length-percentage></a>) 
     <tr>
      <th><a href="https://drafts.csswg.org/css-cascade/#computed">Computed value:</a>
      <td>as specified, with <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage①⑧">&lt;length-percentage></a> values computed 
     <tr>
      <th><a href="https://drafts.csswg.org/web-animations/#animation-type">Animation type:</a>
      <td>by computed value type 
   </table>
   <p>When  used as values for <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-multicol-1/#propdef-column-width" id="ref-for-propdef-column-width②">column-width</a>,
		the new keywords specify the optimal column width: </p>
   <dl>
    <dt><dfn class="dfn-paneled css" data-dfn-for="column-width" data-dfn-type="value" data-export id="valdef-column-width-min-content">min-content</dfn> 
    <dd>Specifies the optimal column width as the <a data-link-type="dfn" href="#min-content-inline-size" id="ref-for-min-content-inline-size">min-content inline size</a> of the multi-column container’s contents. 
    <dt><dfn class="dfn-paneled css" data-dfn-for="column-width" data-dfn-type="value" data-export id="valdef-column-width-max-content">max-content</dfn> 
    <dd>Specifies the optimal column width as the <a data-link-type="dfn" href="#max-content-inline-size" id="ref-for-max-content-inline-size">max-content inline size</a> of the multi-column container’s contents. 
    <dt><dfn class="dfn-paneled css" data-dfn-for="column-width" data-dfn-type="value" data-export id="valdef-column-width-fit-content-length-percentage">fit-content(<a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage①⑨">&lt;length-percentage></a>)</dfn> 
    <dd> Specifies the optimal column width as <code>min(<a data-link-type="dfn" href="#max-content" id="ref-for-max-content④">max-content size</a>, max(<a data-link-type="dfn" href="#min-content" id="ref-for-min-content⑤">min-content size</a>, <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage" id="ref-for-typedef-length-percentage②⓪">&lt;length-percentage></a>))</code> 
   </dl>
   <p class="note" role="note"><span>Note:</span> The column width never varies by column.
	When the column width is informed by the multi-column container’s contents
	(as in the keywords above),
	all of its contents are taken under consideration
	and the calculated width is shared by all the columns.</p>
   <h2 class="heading settled" data-level="4" id="intrinsic"><span class="secno">4. </span><span class="content"> Intrinsic Size Determination</span><a class="self-link" href="#intrinsic"></a></h2>
   <p> <dfn data-dfn-type="dfn" data-export id="intrinsic-sizing">Intrinsic sizing<a class="self-link" href="#intrinsic-sizing"></a></dfn> determines sizes based on the contents of an element,
		without regard for its context. </p>
   <h3 class="heading settled" data-level="4.1" id="intrinsic-sizes"><span class="secno">4.1. </span><span class="content"> Intrinsic Sizes</span><a class="self-link" href="#intrinsic-sizes"></a></h3>
   <p>The <a data-link-type="dfn" href="#min-content" id="ref-for-min-content⑥">min-content size</a> of a box in each axis
	is the size it would have if it was
	a float given an <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto⑨">auto</a> size in that axis
	(and no <a data-link-type="dfn" href="#min-width" id="ref-for-min-width①">minimum</a> or <a data-link-type="dfn" href="#max-width" id="ref-for-max-width①">maximum size</a> in that axis)
	and if its containing block was <em>zero</em>-sized in that axis.
	(In other words, the minimum size it has when sized as “shrink-to-fit”.)</p>
   <p>The <a data-link-type="dfn" href="#max-content" id="ref-for-max-content⑤">max-content size</a> of a box in each axis
	is the size it would have if it was
	a float given an <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto①⓪">auto</a> size in that axis
	(and no <a data-link-type="dfn" href="#min-width" id="ref-for-min-width②">minimum</a> or <a data-link-type="dfn" href="#max-width" id="ref-for-max-width②">maximum size</a> in that axis),
	and if its containing block was <em>infinitely</em>-sized in that axis.
	(In other words, the maximum size it has when sized as “shrink-to-fit”.)</p>
   <p>The <a data-link-type="dfn" href="#min-content" id="ref-for-min-content⑦">min-content size</a> and <a data-link-type="dfn" href="#max-content" id="ref-for-max-content⑥">max-content size</a> are collectively referred to
	as the <dfn data-dfn-type="dfn" data-export id="dfn-intrinsic-sizes">intrinsic sizes<a class="self-link" href="#dfn-intrinsic-sizes"></a></dfn>.</p>
   <p class="note" role="note"><span>Note:</span> Note that when the box has an intrinsic aspect ratio,
	size constraints in the opposite dimension will transfer through
	and can affect the <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto①①">auto</a> size in the considered one.
	See <a href="https://www.w3.org/TR/CSS2/visudet.html">CSS2§10</a>.</p>
   <p>For replaced elements,
	if the <a data-link-type="dfn" href="#max-content" id="ref-for-max-content⑦">max-content size</a> size would depend
	on the size of the containing block
	(as it does for images with an intrinsic aspect ratio but no intrinsic size,
	see <a href="https://www.w3.org/TR/CSS2/visudet.html#inline-replaced-width">CSS2§10.3.2</a>)
	and therefore can’t be calculated against an infinitely-sized containing block
	then:</p>
   <dl>
    <dt>For boxes with an intrinsic aspect ratio, but no intrinsic size: 
    <dd>
     <ul>
      <li data-md>
       <p>If the <a data-link-type="dfn" href="#available" id="ref-for-available⑨">available space</a> is <a data-link-type="dfn" href="#definite" id="ref-for-definite⑥">definite</a> in the <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#inline-axis" id="ref-for-inline-axis②">inline axis</a>,
use the <a data-link-type="dfn" href="#stretch-fit" id="ref-for-stretch-fit②">stretch fit</a> into that size for the inline size
and calculate the block size using the aspect ratio.</p>
      <li data-md>
       <p>Otherwise
if the box has a <a data-link-type="dfn" href="#definite" id="ref-for-definite⑦">definite</a> value for <a class="property" data-link-type="propdesc" href="#propdef-min-width" id="ref-for-propdef-min-width⑤">min-width</a> or <a class="property" data-link-type="propdesc" href="#propdef-min-height" id="ref-for-propdef-min-height⑤">min-height</a>,
use that size and calculate the other dimension using the aspect ratio;
if both dimensions have a definite minimum,
choose the one that results in the larger overall size.</p>
       <p class="note" role="note"><span>Note:</span> This case was previous calculated from a 300x150 default size,
rather than the box’s min size.
This is believed to be a better behavior,
and likely to be web compatible,
but please send feedback to the CSSWG if there are any problems.</p>
      <li data-md>
       <p>Otherwise
use a width of <span class="css">300px</span> (height of <span class="css">150px</span> in <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#vertical-writing-mode" id="ref-for-vertical-writing-mode">vertical writing modes</a>)
and calculate the other dimension using the aspect ratio.</p>
     </ul>
    <dt>For boxes without an intrinsic aspect ratio: 
    <dd>
     <ul>
      <li data-md>
       <p>If the <a data-link-type="dfn" href="#available" id="ref-for-available①⓪">available space</a> is <a data-link-type="dfn" href="#definite" id="ref-for-definite⑧">definite</a> in the appropriate dimension,
use the <a data-link-type="dfn" href="#stretch-fit" id="ref-for-stretch-fit③">stretch fit</a> into that size in that dimension.</p>
      <li data-md>
       <p>Otherwise,
if the box has a <a data-link-type="dfn" href="#definite" id="ref-for-definite⑨">definite</a> non-zero minimum size (<a class="property" data-link-type="propdesc" href="#propdef-min-width" id="ref-for-propdef-min-width⑥">min-width</a>/<a class="property" data-link-type="propdesc" href="#propdef-min-height" id="ref-for-propdef-min-height⑥">min-height</a>) in that dimension,
use that size.</p>
      <li data-md>
       <p>Otherwise,
use <span class="css">300px</span> for the width
and/or <span class="css">150px</span> for the height
as needed.</p>
     </ul>
   </dl>
   <p>Since a block-level or inline-level replaced element
	whose <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height①④">height</a> or <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width①⑥">width</a> <a data-link-type="dfn" href="#behave-as-auto" id="ref-for-behave-as-auto①">behaves as auto</a> is effectively defined to use its <a data-link-type="dfn" href="#max-content" id="ref-for-max-content⑧">max-content size</a> (<a href="https://www.w3.org/TR/CSS2/visudet.html#inline-replaced-width">CSS2§10.3.2</a>),
	this specification applies the rules above
	to the undefined case of a replaced element
	whose <span class="property" id="ref-for-propdef-height①⑤">height</span> and <span class="property" id="ref-for-propdef-width①⑦">width</span> both <span id="ref-for-behave-as-auto②">behave as auto</span>.</p>
   <p class="note" role="note"><span>Note:</span> This specification does not define how to determine
	the size of a float.
	Please refer to <a data-link-type="biblio" href="#biblio-css2">[CSS2]</a>,
	the relevant CSS specification for that display type,
	and/or existing implementations
	for further details.
	A future specification will define this in detail,
	replacing the CSS2 “definition”,
	such as it is.</p>
   <hr>
   <p>Although the <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto①②">auto</a> size of text input controls
	such as HTML’s <code>&lt;input type=text></code> and <code>&lt;textarea></code> elements
	is typically a fixed size,
	the contents of such elements can be used to determine a content-based intrinsic size,
	as for non-replaced block containers.
	The <a class="css" data-link-type="maybe" href="#valdef-width-min-content" id="ref-for-valdef-width-min-content⑤">min-content</a> and <a class="css" data-link-type="maybe" href="#valdef-width-max-content" id="ref-for-valdef-width-max-content④">max-content</a> keywords of the <a data-link-type="dfn" href="#sizing-property" id="ref-for-sizing-property④">sizing properties</a> thus represent content-based sizes
	for form controls which render their value
	as text contained within their box,
	allowing such controls to size to fit their visible contents
	similarly to regular non-replaced elements.</p>
   <p>The content in this case is defined to be the input control’s values
	(the <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/form-elements.html#concept-textarea-raw-value" id="ref-for-concept-textarea-raw-value">raw value</a> in the case of <code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/form-elements.html#the-textarea-element" id="ref-for-the-textarea-element">textarea</a></code>,
	or the <a href="https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#concept-fe-value">value</a> in the case of <code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/input.html#the-input-element" id="ref-for-the-input-element">input</a></code>),
	possibly transformed to a more human-readable and/or localized display format,
	which is then treated as child <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#text-run" id="ref-for-text-run">text runs</a> of the input control,
	allowing <a data-link-type="dfn" href="https://drafts.csswg.org/css-text-3/#soft-wrap-opportunity" id="ref-for-soft-wrap-opportunity">soft wrap opportunities</a> only where the input control would actually allow wrapping
	(whether keyed off of CSS properties or other, UA-internal constraints).
	If the input control has designated placeholder text
	to be overlaid in its value display area,
	then that text is also measured for the purpose of calculating the content-based size—<wbr>whether or not the placeholder text is visible at the moment.
	(Thus the content-based intrinsic size of the input control
	is the larger of the size to fit the placeholder text and the size to fit the value.)</p>
   <p>The UA may enforce a minimum
	(such as the size required to contain a single zero-width character,
	or the smallest usable size of a touch target)
	on the form control’s <a data-link-type="dfn" href="#min-content" id="ref-for-min-content⑧">min-content</a> and <a data-link-type="dfn" href="#max-content" id="ref-for-max-content⑨">max-content sizes</a> to ensure sufficient space for the caret
	and otherwise maintain usability of the form control.</p>
   <p class="note" role="note"><span>Note:</span> This might be extended to <code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/iframe-embed-object.html#the-iframe-element" id="ref-for-the-iframe-element">iframe</a></code> or other content-containing replaced elements
	(see <a href="https://github.com/w3c/csswg-drafts/issues/1771">discussion</a>),
	but text inputs are a major use-case;
	and being document-internal,
	have the least additional complications.</p>
   <h3 class="heading settled" data-level="4.2" id="intrinsic-contribution"><span class="secno">4.2. </span><span class="content"> Intrinsic Contributions</span><a class="self-link" href="#intrinsic-contribution"></a></h3>
   <p>A box’s <a data-link-type="dfn" href="#min-content-contribution" id="ref-for-min-content-contribution③">min-content contribution</a>/<a data-link-type="dfn" href="#max-content-contribution" id="ref-for-max-content-contribution③">max-content contribution</a> in each axis
	is the size of the content box
	of a hypothetical <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto①③">auto</a>-sized float
	that contains only that box,
	if that hypothetical float’s containing block is zero-sized/infinitely-sized.</p>
   <p class="note" role="note"><span>Note:</span> This specification does not define precisely how to determine these sizes.
	Please refer to <a data-link-type="biblio" href="#biblio-css2">[CSS2]</a>,
	the relevant CSS specification for that display type,
	the <a href="#percentage-sizing">rules for handling percentages</a> (below),
	and/or existing implementations
	for further details.</p>
   <h2 class="heading settled" data-level="5" id="extrinsic"><span class="secno">5. </span><span class="content"> Extrinsic Size Determination</span><a class="self-link" href="#extrinsic"></a></h2>
   <p> <dfn data-dfn-type="dfn" data-export id="extrinsic-sizing">Extrinsic sizing<a class="self-link" href="#extrinsic-sizing"></a></dfn> determines sizes based on the context of an element,
		without regard for its contents. </p>
   <h3 class="heading settled" data-level="5.1" id="percentage-sizing"><span class="secno">5.1. </span><span class="content"> Percentage Sizing</span><a class="self-link" href="#percentage-sizing"></a></h3>
   <p>Percentages specify sizing of a box with respect to the box’s <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#containing-block" id="ref-for-containing-block①①">containing block</a>.</p>
   <div class="example" id="example-65abfbed">
    <a class="self-link" href="#example-65abfbed"></a> For example, in the following markup: 
<pre class="lang-html highlight"><c- p>&lt;</c-><c- f>article</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 60em"</c-><c- p>></c->
  <c- p>&lt;</c-><c- f>figure</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 50%;"</c-><c- p>></c->
    <c- p>&lt;</c-><c- f>img</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 50%;"</c-><c- p>></c->
  <c- p>&lt;/</c-><c- f>figure</c-><c- p>></c->
<c- p>&lt;/</c-><c- f>article</c-><c- p>></c->
</pre>
    <ul>
     <li data-md>
      <p>the <code>&lt;figure></code> would be <span class="css">30em</span> tall
= 50% of the <a data-link-type="dfn" href="#definite" id="ref-for-definite①⓪">definite</a> <span class="css">60em</span> height of the <code>&lt;article></code></p>
     <li data-md>
      <p>the <code>&lt;img></code> would be <span class="css">15em</span> tall
= 50% of the <code>&lt;figure></code>’s height
(which is itself <a data-link-type="dfn" href="#definite" id="ref-for-definite①①">definite</a> because it’s a percentage resolved against a <span id="ref-for-definite①②">definite</span> length)</p>
    </ul>
   </div>
   <p>Sometimes the size of a percentage-sized box’s <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#containing-block" id="ref-for-containing-block①②">containing block</a> depends on the intrinsic size contribution of the box itself,
	creating a cyclic dependency.
	When calculating the <a data-link-type="dfn" href="#intrinsic-size-contribution" id="ref-for-intrinsic-size-contribution①">intrinsic size contribution</a> of such a box
	(including any calculations for a content-based <a data-link-type="dfn" href="#automatic-minimum-size" id="ref-for-automatic-minimum-size">automatic minimum size</a>),
	a <dfn class="dfn-paneled" data-dfn-type="dfn" data-noexport id="cyclic-percentage">cyclic percentage</dfn>—<wbr>that is,
	a percentage value that would resolve against a containing block size
	which itself depends on that percentage—<wbr>is resolved specially:</p>
   <ol type="a">
    <li id="non-replaced-percentage-contribution"><a class="self-link" href="#non-replaced-percentage-contribution"></a> If the box is <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#non-replaced" id="ref-for-non-replaced①">non-replaced</a>,
		then the entire value of any <a data-link-type="dfn" href="#max-size-properties" id="ref-for-max-size-properties">max size property</a> or <a data-link-type="dfn" href="#preferred-size-properties" id="ref-for-preferred-size-properties">preferred size property</a> (<a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width①⑧">width</a>/<a class="property" data-link-type="propdesc" href="#propdef-max-width" id="ref-for-propdef-max-width④">max-width</a>/<a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height①⑥">height</a>/<a class="property" data-link-type="propdesc" href="#propdef-max-height" id="ref-for-propdef-max-height④">max-height</a>)
		specified as an expression containing a percentage
		(such as <span class="css">10%</span> or <span class="css">calc(10px + 0%)</span>)
		that is <a data-link-type="dfn" href="#cyclic-percentage" id="ref-for-cyclic-percentage">cyclic</a> is treated <em>for the purpose of calculating the box’s intrinsic size contributions only</em> as that property’s <a data-link-type="dfn" href="https://drafts.csswg.org/css-cascade-4/#initial-value" id="ref-for-initial-value">initial value</a>.
		For example, given a box with <span class="css" id="ref-for-propdef-width①⑨">width: calc(20px + 50%)</span>,
		its max-content contribution is calculated as if its <span class="property" id="ref-for-propdef-width②⓪">width</span> were <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto①④">auto</a>.
		(The percentage is honored as usual, however,
		during the actual sizing of the box itself; see below.) 
    <li id="replaced-percentage-max-contribution"><a class="self-link" href="#replaced-percentage-max-contribution"></a> Likewise, if the box is <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#replaced-element" id="ref-for-replaced-element">replaced</a>,
		then the entire value of any <a data-link-type="dfn" href="#max-size-properties" id="ref-for-max-size-properties①">max size property</a> or <a data-link-type="dfn" href="#preferred-size-properties" id="ref-for-preferred-size-properties①">preferred size property</a> specified as an expression containing a percentage
		that is <a data-link-type="dfn" href="#cyclic-percentage" id="ref-for-cyclic-percentage①">cyclic</a> is treated <em>for the purpose of calculating the box’s <a data-link-type="dfn" href="#max-content-contribution" id="ref-for-max-content-contribution④">max-content contributions</a> only</em> as that property’s <a data-link-type="dfn" href="https://drafts.csswg.org/css-cascade-4/#initial-value" id="ref-for-initial-value①">initial value</a>. 
    <li id="replaced-percentage-min-contribution">
     <a class="self-link" href="#replaced-percentage-min-contribution"></a> If the box is <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#replaced-element" id="ref-for-replaced-element①">replaced</a>,
		a <a data-link-type="dfn" href="#cyclic-percentage" id="ref-for-cyclic-percentage②">cyclic percentage</a> in the value of any <a data-link-type="dfn" href="#max-size-properties" id="ref-for-max-size-properties②">max size property</a> or <a data-link-type="dfn" href="#preferred-size-properties" id="ref-for-preferred-size-properties②">preferred size property</a> (<a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width②①">width</a>/<a class="property" data-link-type="propdesc" href="#propdef-max-width" id="ref-for-propdef-max-width⑤">max-width</a>/<a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height①⑦">height</a>/<a class="property" data-link-type="propdesc" href="#propdef-max-height" id="ref-for-propdef-max-height⑤">max-height</a>),
		is resolved against zero
		when calculating the <a data-link-type="dfn" href="#min-content-contribution" id="ref-for-min-content-contribution④">min-content contribution</a> in the corresponding axis.
		(See <a href="#min-content-zero">Compressible Replaced Elements</a> for a list of which elements in HTML this applies to.)
		The UA may additionally floor this size based on UI considerations,
		such as ensuring certain UI elements remain visible
		(for example, the dropdown arrow on a <code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/form-elements.html#the-select-element" id="ref-for-the-select-element">select</a></code>).
		This rule also applies when calculating
		a content-based <a data-link-type="dfn" href="#automatic-minimum-size" id="ref-for-automatic-minimum-size①">automatic minimum size</a> or its corresponding size contribution,
		yielding a <a data-link-type="dfn" href="#definite" id="ref-for-definite①③">definite</a> “specified size suggestion”. 
     <div class="example" id="example-b06093ff"><a class="self-link" href="#example-b06093ff"></a> For example,
			an <code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/input.html#the-input-element" id="ref-for-the-input-element①">input</a></code> assigned <a class="css" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width②②">width: calc(50% + 50px)</a> has a <a data-link-type="dfn" href="#min-content-contribution" id="ref-for-min-content-contribution⑤">min-content contribution</a> of <span class="css">50px</span>,
			plus any horizontal margin/border/padding. </div>
     <p class="note" role="note"><span>Note:</span> We are not 100% sure if zeroing out a percentage <a class="property" data-link-type="propdesc" href="#propdef-max-width" id="ref-for-propdef-max-width⑥">max-width</a> on form controls is web-compatible.
		See <a href="https://github.com/w3c/csswg-drafts/issues/765">Issue 765</a>.</p>
    <li id="min-percentage-contribution"><a class="self-link" href="#min-percentage-contribution"></a> For the <a data-link-type="dfn" href="#min-size-properties" id="ref-for-min-size-properties">min size properties</a>,
		as well as for margins and paddings,
		a <a data-link-type="dfn" href="#cyclic-percentage" id="ref-for-cyclic-percentage③">cyclic percentage</a> is resolved against zero
		for determining intrinsic size contributions. 
   </ol>
   <table class="data">
    <caption>Summary of the Cyclic-Percentage Intrinsic Size Contribution Rules (Above)</caption>
    <colgroup span="1">
    <colgroup span="2">
    <colgroup span="2">
    <thead>
     <tr>
      <th scope="row">Element Type 
      <th colspan="2" scope="colgroup"><a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#replaced-element" id="ref-for-replaced-element②">Replaced</a> 
      <th colspan="2" scope="colgroup"><a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#non-replaced" id="ref-for-non-replaced②">Non-replaced</a> 
     <tr>
      <th scope="row">Contribution Type 
      <th scope="col"><a data-link-type="dfn" href="#min-content-contribution" id="ref-for-min-content-contribution⑥">min-content</a> 
      <th scope="col"><a data-link-type="dfn" href="#max-content-contribution" id="ref-for-max-content-contribution⑤">max-content</a> 
      <th scope="col"><a data-link-type="dfn" href="#min-content-contribution" id="ref-for-min-content-contribution⑦">min-content</a> 
      <th scope="col"><a data-link-type="dfn" href="#max-content-contribution" id="ref-for-max-content-contribution⑥">max-content</a> 
    <tbody>
     <tr>
      <th scope="row"><a data-link-type="dfn" href="#min-size-properties" id="ref-for-min-size-properties①">min size</a> &amp; <a data-link-type="dfn" href="https://drafts.csswg.org/css-box-3/#margin-properties" id="ref-for-margin-properties">margin</a>/<a data-link-type="dfn" href="https://drafts.csswg.org/css-box-3/#padding-properties" id="ref-for-padding-properties">padding</a> 
      <td><a href="#min-percentage-contribution">zeroᵈ</a> 
      <td><a href="#min-percentage-contribution">zeroᵈ</a> 
      <td><a href="#min-percentage-contribution">zeroᵈ</a> 
      <td><a href="#min-percentage-contribution">zeroᵈ</a> 
     <tr>
      <th scope="row"><a data-link-type="dfn" href="#max-size-properties" id="ref-for-max-size-properties③">max</a> &amp; <a data-link-type="dfn" href="#preferred-size-properties" id="ref-for-preferred-size-properties③">preferred size</a> 
      <td><a href="#replaced-percentage-min-contribution">zeroᶜ</a> 
      <td><a href="#replaced-percentage-max-contribution">initialᵇ</a> 
      <td><a href="#non-replaced-percentage-contribution">initialᵃ</a> 
      <td><a href="#non-replaced-percentage-contribution">initialᵃ</a> 
   </table>
   <p>Then, unless otherwise specified,
	when calculating the used sizes and positions of the containing block’s <em>contents</em>:</p>
   <ul>
    <li data-md>
     <p>If the cyclic dependency was introduced due to
a <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-logical-1/#propdef-block-size" id="ref-for-propdef-block-size">block-size</a> or <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-logical-1/#propdef-max-block-size" id="ref-for-propdef-max-block-size">max-block-size</a> on the containing block
that causes it to depend on the size of its contents,
the box’s percentage is not resolved and instead <a data-link-type="dfn" href="#behave-as-auto" id="ref-for-behave-as-auto③">behaves as auto</a>.</p>
     <p class="note" role="note"><span>Note:</span> <a data-link-type="dfn" href="https://drafts.csswg.org/css-grid-1/#grid-item" id="ref-for-grid-item">Grid items</a> and <a data-link-type="dfn" href="https://drafts.csswg.org/css-flexbox-1/#flex-item" id="ref-for-flex-item">flex items</a> do allow percentages to resolve in this case.</p>
    <li data-md>
     <p>Otherwise, the percentage is resolved against the containing block’s size.
(The containing block’s size is not re-resolved based on the resulting size of the box;
the contents might thus overflow or underflow the containing block).</p>
   </ul>
   <p class="note" role="note"><span>Note:</span> These rules specify the previously-undefined behavior of this cyclic case
	in <a href="https://www.w3.org/TR/CSS2/visudet.html#the-width-property">CSS2§10.2</a>, <a href="https://www.w3.org/TR/CSS2/box.html#margin-properties">CSS2§8.3</a>,
	and <a href="https://www.w3.org/TR/CSS2/box.padding-properties">CSS2§8.4</a>.
	Note also, the behavior in <a href="https://www.w3.org/TR/CSS2/visudet.html#the-height-property">CSS2§10.5</a> is superseded in their respective specifications for layout modes
	(such as <a href="http://www.w3.org/TR/css-flexbox/">flex layout</a>)
	not described in CSS2.</p>
   <div class="example" id="example-a57016da">
    <a class="self-link" href="#example-a57016da"></a> For example, in the following markup: 
<pre class="lang-html highlight"><c- p>&lt;</c-><c- f>article</c-> <c- e>style</c-><c- o>=</c-><c- s>"width: min-content"</c-><c- p>></c->
  <c- p>&lt;</c-><c- f>aside</c-> <c- e>style</c-><c- o>=</c-><c- s>"width: 50%;"</c-><c- p>></c->
  LOOOOOOOOOOOOOOOOOOOONG
  <c- p>&lt;/</c-><c- f>aside</c-><c- p>></c->
<c- p>&lt;/</c-><c- f>article</c-><c- p>></c->
</pre>
    <p>When calculating the width of the outer <code>&lt;article></code>,
		the inner <code>&lt;aside></code> behaves as <a class="css" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width②③">width: auto</a>,
		so the <code>&lt;article></code> sets itself to the width of the long word.
		Since the <code>&lt;article></code>’s width didn’t depend on "real" layout,
		though, it’s treated as <a data-link-type="dfn" href="#definite" id="ref-for-definite①④">definite</a> for resolving the <code>&lt;aside></code>,
		whose width resolves to half that of the <code>&lt;article></code>.</p>
   </div>
   <div class="example" id="example-a6fc9bae">
    <a class="self-link" href="#example-a6fc9bae"></a> In this example, 
<pre class="lang-html highlight"><c- p>&lt;</c-><c- f>article</c-> <c- e>style</c-><c- o>=</c-><c- s>"height:auto"</c-><c- p>></c->
  <c- p>&lt;</c-><c- f>aside</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 50%;"</c-><c- p>></c->
    <c- p>&lt;</c-><c- f>div</c-> <c- e>class</c-><c- o>=</c-><c- s>block</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 150px;"</c-><c- p>>&lt;/</c-><c- f>div</c-><c- p>></c->
  <c- p>&lt;/</c-><c- f>aside</c-><c- p>></c->
  <c- p>&lt;</c-><c- f>section</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 30px;"</c-><c- p>>&lt;/</c-><c- f>section</c-><c- p>></c->
<c- p>&lt;/</c-><c- f>article</c-><c- p>></c->
</pre>
    <p>because the percentage <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-4/#block-size" id="ref-for-block-size⑤">block size</a> (<a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height①⑧">height</a>, in this case) on block-level elements
		is defined to not resolve inside content-sized containing blocks,
		the percentage height on the <code>&lt;aside></code> is ignored,
		that is, it behaves exactly as if <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto①⑤">auto</a> were specified.</p>
   </div>
   <div class="example" id="example-8559f728">
    <a class="self-link" href="#example-8559f728"></a> 
    <p class="issue" id="issue-9b3707fe"><a class="self-link" href="#issue-9b3707fe"></a> Letting percentages still resolve against a definite <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height①⑨">height</a> when the min-height is intrinsic is an open issue.
		(CSS2 has a general statement about "height depending on contents",
		which this technically is,
		even though CSS2 didn’t have content-dependent keywords for <a class="property" data-link-type="propdesc" href="#propdef-min-height" id="ref-for-propdef-min-height⑦">min-height</a>.
		Since this is new, we think we could have this different behavior.)</p>
    <p>The following examples illustrate how block-axis percentages resolve against a containing block whose size depends on its contents.</p>
<pre class="lang-html highlight"><c- p>&lt;</c-><c- f>article</c-> <c- e>style</c-><c- o>=</c-><c- s>"height:100px; min-height: min-content;"</c-><c- p>></c->
  <c- p>&lt;</c-><c- f>aside</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 50%;"</c-><c- p>></c->
    <c- p>&lt;</c-><c- f>div</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 150px;"</c-><c- p>>&lt;/</c-><c- f>div</c-><c- p>></c->
  <c- p>&lt;/</c-><c- f>aside</c-><c- p>></c->
  <c- p>&lt;</c-><c- f>section</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 30px;"</c-><c- p>>&lt;/</c-><c- f>section</c-><c- p>></c->
<c- p>&lt;/</c-><c- f>article</c-><c- p>></c->
</pre>
    <p>The initial height of the <code>&lt;article></code> is 100px, as specified,
		which would make the <code>&lt;aside></code> 50px tall
		when it resolved its percentage.
		However, we must calculate the min-height,
		by substituting it in for <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height②⓪">height</a>.
		This causes the percentage on the <code>&lt;aside></code> to <a data-link-type="dfn" href="#behave-as-auto" id="ref-for-behave-as-auto④">behave as auto</a>,
		so the <code>&lt;aside></code> ends up 150px tall.
		The total height of the contents is thus 180px.
		This is larger than the specified 100px height,
		so the <code>&lt;article></code> gets adjusted to 180px tall.</p>
    <p>Then, since the percentage could <em>originally</em> resolve against the (100px) height,
		it now resolves against the 180px height,
		so the <code>&lt;aside></code> ends up being 90px tall.</p>
<pre class="lang-html highlight"><c- p>&lt;</c-><c- f>article</c-> <c- e>style</c-><c- o>=</c-><c- s>"height:auto; min-height: min-content;"</c-><c- p>></c->
  <c- p>&lt;</c-><c- f>aside</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 50%;"</c-><c- p>></c->
    <c- p>&lt;</c-><c- f>div</c-> <c- e>class</c-><c- o>=</c-><c- s>block</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 150px;"</c-><c- p>>&lt;/</c-><c- f>div</c-><c- p>></c->
  <c- p>&lt;/</c-><c- f>aside</c-><c- p>></c->
  <c- p>&lt;</c-><c- f>section</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 30px;"</c-><c- p>>&lt;/</c-><c- f>section</c-><c- p>></c->
<c- p>&lt;/</c-><c- f>article</c-><c- p>></c->
</pre>
    <p>In this case, the percentage on the <code>&lt;aside></code> won’t normally resolve,
		because the containing block’s height is <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto①⑥">auto</a> (and thus depends on the size of its contents).
		Instead it <a data-link-type="dfn" href="#behave-as-auto" id="ref-for-behave-as-auto⑤">behaves as auto</a>,
		resulting in a height of 150px for the <code>&lt;aside></code>,
		and an initial height of 180px for the <code>&lt;article></code> The <a class="property" data-link-type="propdesc" href="#propdef-min-height" id="ref-for-propdef-min-height⑧">min-height</a> doesn’t change this; <a class="css" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height②①">height: min-content;</a> acts similarly to <span class="css" id="ref-for-propdef-height②②">height: auto;</span> and results in the same sizes.</p>
<pre class="lang-html highlight"><c- p>&lt;</c-><c- f>article</c-> <c- e>style</c-><c- o>=</c-><c- s>"height:100px; min-height: min-content;"</c-><c- p>></c->
  <c- p>&lt;</c-><c- f>aside</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 200%;"</c-><c- p>></c->
    <c- p>&lt;</c-><c- f>div</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 150px;"</c-><c- p>>&lt;/</c-><c- f>div</c-><c- p>></c->
  <c- p>&lt;/</c-><c- f>aside</c-><c- p>></c->
  <c- p>&lt;</c-><c- f>section</c-> <c- e>style</c-><c- o>=</c-><c- s>"height: 30px;"</c-><c- p>>&lt;/</c-><c- f>section</c-><c- p>></c->
<c- p>&lt;/</c-><c- f>article</c-><c- p>></c->
</pre>
    <p>This is a variation on the first code block,
		and follows a similar path;
		the <code>&lt;aside></code> initially wants to compute to 200px tall
		(200% of the 100px containing block height).
		When we calculate the effects of <a class="property" data-link-type="propdesc" href="#propdef-min-height" id="ref-for-propdef-min-height⑨">min-height</a>,
		the percentage <a data-link-type="dfn" href="#behave-as-auto" id="ref-for-behave-as-auto⑥">behaves as auto</a>,
		causing it to become 150px tall,
		and the total <a class="css" data-link-type="maybe" href="#valdef-width-min-content" id="ref-for-valdef-width-min-content⑥">min-content</a> height of the containing block
		to be 180px tall.
		Since this is larger than 100px,
		the <code>&lt;article></code> gets clamped to 180px,
		the percentage resolves against this new height,
		and the <code>&lt;aside></code> ends up being 360px tall,
		overflowing the <code>&lt;article></code></p>
   </div>
   <h2 class="no-num heading settled" id="min-content-zero"><span class="content"> Compressible Replaced Elements</span><a class="self-link" href="#min-content-zero"></a></h2>
   <p>The following elements can have their <a data-link-type="dfn" href="#min-content" id="ref-for-min-content⑨">min-content size</a> compressed
	when their <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width②④">width</a>/<a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height②③">height</a> or <a class="property" data-link-type="propdesc" href="#propdef-max-width" id="ref-for-propdef-max-width⑦">max-width</a>/<a class="property" data-link-type="propdesc" href="#propdef-max-height" id="ref-for-propdef-max-height⑥">max-height</a> is expressed with a percentage size.
	See <a href="#intrinsic-contribution">§ 4.2 Intrinsic Contributions</a>.</p>
   <ul>
    <li data-md>
     <p>All <a data-link-type="dfn" href="https://drafts.csswg.org/css-display-3/#replaced-element" id="ref-for-replaced-element③">replaced elements</a> that aren’t form controls.
See <a href="https://html.spec.whatwg.org/multipage/rendering.html#replaced-elements">HTML§14.4</a>. <a data-link-type="biblio" href="#biblio-html">[HTML]</a></p>
    <li data-md>
     <p><code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/input.html#the-input-element" id="ref-for-the-input-element②">input</a></code> with any <code><a data-link-type="element-sub" href="https://html.spec.whatwg.org/multipage/input.html#attr-input-type" id="ref-for-attr-input-type">type</a></code> that is not "button-like";
this can vary depending on the UA.</p>
     <p>A type is "button-like" in a particular UA if it displays similar to a <code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/form-elements.html#the-button-element" id="ref-for-the-button-element①">button</a></code> element,
where it can contains actual content that determines the layout of the element.
In most UAs, the "button", "reset", "submit", and "color" types are button-like;
the "file" type is also partially button-like in some UAs,
when it’s displayed as a combination of a text input (shrinkable)
and a button (button-like, and thus not shrinkable).</p>
    <li data-md>
     <p><code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/form-elements.html#the-select-element" id="ref-for-the-select-element①">select</a></code>, <code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/form-elements.html#the-textarea-element" id="ref-for-the-textarea-element①">textarea</a></code>, <code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/form-elements.html#the-progress-element" id="ref-for-the-progress-element">progress</a></code>, <code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/form-elements.html#the-meter-element" id="ref-for-the-meter-element">meter</a></code>.</p>
   </ul>
   <h2 class="no-num heading settled" id="changes"><span class="content"> Changes</span><a class="self-link" href="#changes"></a></h2>
   <p> Major changes since the <a href="https://www.w3.org/TR/2018/WD-css-sizing-3-20180304/">4 March 2018 Working Draft</a> include: </p>
   <ul>
    <li>Imported the <a class="property" data-link-type="propdesc" href="#propdef-box-sizing" id="ref-for-propdef-box-sizing⑦">box-sizing</a> definition from <a href="https://www.w3.org/TR/css-ui-3/">CSS UI Level 3</a>. 
    <li>More rigorously specified handling of <a data-link-type="dfn" href="#cyclic-percentage" id="ref-for-cyclic-percentage④">cyclic percentages</a>.
			(<a href="https://github.com/w3c/csswg-drafts/issues/1132">#1132</a>, <a href="https://github.com/w3c/csswg-drafts/issues/2384">#2384</a>, <a href="https://github.com/w3c/csswg-drafts/issues/2297">#2297</a>, <a href="https://github.com/w3c/csswg-drafts/issues/2674">#2674</a>) 
    <li>Changed the <span class="css">*-content</span> values applied to the bock axis
			to not compute to the property’s initial value,
			but to rather “behave as” the property’s initial value.
			(<a href="https://github.com/w3c/csswg-drafts/issues/2708">#2708</a>) 
    <li>Fixed miscellaneous trivial errors. 
   </ul>
   <p> Major changes since the <a href="https://www.w3.org/TR/2017/WD-css-sizing-3-20170207/">7 February 2017 Working Draft</a> include: </p>
   <ul>
    <li>More accurate definition of min-content and max-content sizes for replaced elements. 
    <li>Compute new keywords to the initial value, not to a potentially non-existent <a class="css" data-link-type="maybe" href="#valdef-width-auto" id="ref-for-valdef-width-auto①⑦">auto</a>, when applied to the block axis. 
    <li>Specify that percent sizes on replaced elements zero out their min-content contribution. 
    <li>Fix confusing/wrong definition of percentage sizes resolved against a dependent containing block.
			(This may require further work.) 
    <li>Deferred the <span class="css">stretch</span> and <span class="css">fit-content</span> keywords to Level 4
			to allow for further consideration of their behavior in <a data-link-type="dfn" href="#indefinite" id="ref-for-indefinite⑥">indefinite</a> containing blocks. 
    <li>Pulled in full definitions for all of the sizing properties (rather than diffing them): <a class="property" data-link-type="propdesc" href="#propdef-width" id="ref-for-propdef-width②⑤">width</a>, <a class="property" data-link-type="propdesc" href="#propdef-height" id="ref-for-propdef-height②④">height</a>, <a class="property" data-link-type="propdesc" href="#propdef-min-width" id="ref-for-propdef-min-width⑦">min-width</a>, <a class="property" data-link-type="propdesc" href="#propdef-min-height" id="ref-for-propdef-min-height①⓪">min-height</a>, max-width', <a class="property" data-link-type="propdesc" href="#propdef-max-height" id="ref-for-propdef-max-height⑦">max-height</a>, and <a class="property" data-link-type="propdesc" href="#propdef-box-sizing" id="ref-for-propdef-box-sizing⑧">box-sizing</a>. 
   </ul>
   <h2 class="no-num heading settled" id="acknowledgments"><span class="content"> Acknowledgments</span><a class="self-link" href="#acknowledgments"></a></h2>
   <p>Special thanks go to
	L. David Baron,
	Aaron Gustafson,
	Daniel Holbert,
	and
	Mats Palmgren
	for their contributions to this module. </p>
   <h2 class="no-num heading settled" id="priv-sec"><span class="content"> Privacy and Security Considerations</span><a class="self-link" href="#priv-sec"></a></h2>
   <p>This specification introduces no new privacy or security considerations.</p>
  </main>
  <h2 class="no-ref no-num heading settled" id="conformance"><span class="content"> Conformance</span><a class="self-link" href="#conformance"></a></h2>
  <h3 class="heading settled" id="document-conventions"><span class="content"> Document conventions</span><a class="self-link" href="#document-conventions"></a></h3>
  <p>Conformance requirements are expressed with a combination of
	descriptive assertions and RFC 2119 terminology. The key words “MUST”,
	“MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”,
	“RECOMMENDED”, “MAY”, and “OPTIONAL” in the normative parts of this
	document are to be interpreted as described in RFC 2119.
	However, for readability, these words do not appear in all uppercase
	letters in this specification. </p>
  <p>All of the text of this specification is normative except sections
	explicitly marked as non-normative, examples, and notes. <a data-link-type="biblio" href="#biblio-rfc2119">[RFC2119]</a> </p>
  <p>Examples in this specification are introduced with the words “for example”
	or are set apart from the normative text with <code>class="example"</code>,
	like this: </p>
  <div class="example" id="example-ae2b6bc0">
   <a class="self-link" href="#example-ae2b6bc0"></a> 
   <p>This is an example of an informative example. </p>
  </div>
  <p>Informative notes begin with the word “Note” and are set apart from the
	normative text with <code>class="note"</code>, like this: </p>
  <p class="note" role="note">Note, this is an informative note. </p>
  <p>Advisements are normative sections styled to evoke special attention and are
	set apart from other normative text with <code>&lt;strong class="advisement"></code>, like
	this: <strong class="advisement"> UAs MUST provide an accessible alternative. </strong> </p>
  <h3 class="heading settled" id="conform-classes"><span class="content"> Conformance classes</span><a class="self-link" href="#conform-classes"></a></h3>
  <p>Conformance to this specification
	is defined for three conformance classes: </p>
  <dl>
   <dt>style sheet 
   <dd>A <a href="http://www.w3.org/TR/CSS2/conform.html#style-sheet">CSS
			style sheet</a>. 
   <dt>renderer 
   <dd>A <a href="http://www.w3.org/TR/CSS2/conform.html#user-agent">UA</a> that interprets the semantics of a style sheet and renders
			documents that use them. 
   <dt>authoring tool 
   <dd>A <a href="http://www.w3.org/TR/CSS2/conform.html#user-agent">UA</a> that writes a style sheet. 
  </dl>
  <p>A style sheet is conformant to this specification
	if all of its statements that use syntax defined in this module are valid
	according to the generic CSS grammar and the individual grammars of each
	feature defined in this module. </p>
  <p>A renderer is conformant to this specification
	if, in addition to interpreting the style sheet as defined by the
	appropriate specifications, it supports all the features defined
	by this specification by parsing them correctly
	and rendering the document accordingly. However, the inability of a
	UA to correctly render a document due to limitations of the device
	does not make the UA non-conformant. (For example, a UA is not
	required to render color on a monochrome monitor.) </p>
  <p>An authoring tool is conformant to this specification
	if it writes style sheets that are syntactically correct according to the
	generic CSS grammar and the individual grammars of each feature in
	this module, and meet all other conformance requirements of style sheets
	as described in this module. </p>
  <h3 class="heading settled" id="conform-responsible"><span class="content"> Requirements for Responsible Implementation of CSS</span><a class="self-link" href="#conform-responsible"></a></h3>
  <p>The following sections define several conformance requirements
		for implementing CSS responsibly,
		in a way that promotes interoperability in the present and future. </p>
  <h4 class="heading settled" id="conform-partial"><span class="content"> Partial Implementations</span><a class="self-link" href="#conform-partial"></a></h4>
  <p>So that authors can exploit the forward-compatible parsing rules to assign fallback values, <strong>CSS renderers <em>must</em> treat as invalid
		(and <a href="http://www.w3.org/TR/CSS2/conform.html#ignore">ignore as appropriate</a>)
		any at-rules, properties, property values, keywords, and other syntactic constructs
		for which they have no usable level of support</strong>.
		In particular, user agents <em>must not</em> selectively ignore
		unsupported property values and honor supported values in a single multi-value property declaration:
		if any value is considered invalid (as unsupported values must be),
		CSS requires that the entire declaration be ignored. </p>
  <h4 class="heading settled" id="conform-future-proofing"><span class="content"> Implementations of Unstable and Proprietary Features</span><a class="self-link" href="#conform-future-proofing"></a></h4>
  <p>To avoid clashes with future stable CSS features,
		the CSSWG recommends <a href="http://www.w3.org/TR/CSS/#future-proofing">following best practices</a> for the implementation of <a href="http://www.w3.org/TR/CSS/#unstable">unstable</a> features and <a href="http://www.w3.org/TR/CSS/#proprietary-extension">proprietary extensions</a> to CSS. </p>
  <h4 class="heading settled" id="conform-testing"><span class="content"> Implementations of CR-level Features</span><a class="self-link" href="#conform-testing"></a></h4>
  <p>Once a specification reaches the Candidate Recommendation stage,
		implementers should release an <a data-link-type="dfn" href="http://www.w3.org/TR/CSS/#vendor-prefix">unprefixed</a> implementation
		of any CR-level feature they can demonstrate
		to be correctly implemented according to spec,
		and should avoid exposing a prefixed variant of that feature. </p>
  <p>To establish and maintain the interoperability of CSS across
		implementations, the CSS Working Group requests that non-experimental
		CSS renderers submit an implementation report (and, if necessary, the
		testcases used for that implementation report) to the W3C before
		releasing an unprefixed implementation of any CSS features. Testcases
		submitted to W3C are subject to review and correction by the CSS
		Working Group. </p>
  <p>
   Further information on submitting testcases and implementation reports
		can be found from on the CSS Working Group’s website at <a href="http://www.w3.org/Style/CSS/Test/">http://www.w3.org/Style/CSS/Test/</a>.
		Questions should be directed to the <a href="http://lists.w3.org/Archives/Public/public-css-testsuite">public-css-testsuite@w3.org</a> mailing list. 
<script src="https://www.w3.org/scripts/TR/2016/fixup.js"></script>
  </p>
  <aside class="caniuse-status" data-deco data-dfn-id="box-sizing">
   <input class="caniuse-panel-btn" type="button" value="⋰">
   <p class="support"><b>Support:</b><span class="android yes"><span>Android Browser</span><span>4+</span></span><span class="baidu yes"><span>Baidu Browser</span><span>7.12+</span></span><span class="bb yes"><span>Blackberry Browser</span><span>10+</span></span><span class="chrome yes"><span>Chrome</span><span>10+</span></span><span class="and_chr yes"><span>Chrome for Android</span><span>74+</span></span><span class="edge yes"><span>Edge</span><span>12+</span></span><span class="firefox yes"><span>Firefox</span><span>29+</span></span><span class="and_ff yes"><span>Firefox for Android</span><span>66+</span></span><span class="ie yes"><span>IE</span><span>8+</span></span><span class="ie_mob yes"><span>IE Mobile</span><span>10+</span></span><span class="kaios yes"><span>KaiOS Browser</span><span>2.5+</span></span><span class="opera yes"><span>Opera</span><span>9.5+</span></span><span class="op_mini yes"><span>Opera Mini</span><span>All</span></span><span class="op_mob yes"><span>Opera Mobile</span><span>10+</span></span><span class="and_qq yes"><span>QQ Browser</span><span>1.2+</span></span><span class="safari yes"><span>Safari</span><span>5.1+</span></span><span class="samsung yes"><span>Samsung Internet</span><span>4+</span></span><span class="and_uc yes"><span>UC Browser for Android</span><span>11.8+</span></span><span class="ios_saf yes"><span>iOS Safari</span><span>5.0+</span></span></p>
   <p class="caniuse">Source: <a href="https://caniuse.com/#feat=css3-boxsizing">caniuse.com</a> as of 2019-06-04</p>
  </aside>
  <h2 class="no-num no-ref heading settled" id="index"><span class="content">Index</span><a class="self-link" href="#index"></a></h2>
  <h3 class="no-num no-ref heading settled" id="index-defined-here"><span class="content">Terms defined by this specification</span><a class="self-link" href="#index-defined-here"></a></h3>
  <ul class="index">
   <li><a href="#valdef-width-auto">auto</a><span>, in §3.2</span>
   <li><a href="#automatic-minimum-size">automatic minimum size</a><span>, in §3.2</span>
   <li><a href="#automatic-size">automatic size</a><span>, in §3.2</span>
   <li><a href="#available">available</a><span>, in §2</span>
   <li><a href="#available">available block space</a><span>, in §2</span>
   <li><a href="#available">available inline space</a><span>, in §2</span>
   <li><a href="#available">available space</a><span>, in §2</span>
   <li><a href="#behave-as-auto">behave as auto</a><span>, in §3.2.1</span>
   <li><a href="#behave-as-auto">behaves as auto</a><span>, in §3.2.1</span>
   <li><a href="#behave-as-auto">behaving as auto</a><span>, in §3.2.1</span>
   <li><a href="#valdef-box-sizing-border-box">border-box</a><span>, in §3.3</span>
   <li><a href="#propdef-box-sizing">box-sizing</a><span>, in §3.3</span>
   <li><a href="#valdef-box-sizing-content-box">content-box</a><span>, in §3.3</span>
   <li><a href="#cyclic-percentage">cyclic percentage</a><span>, in §5.1</span>
   <li><a href="#definite">definite</a><span>, in §2</span>
   <li><a href="#definite">definite size</a><span>, in §2</span>
   <li><a href="#extrinsic-sizing">Extrinsic sizing</a><span>, in §5</span>
   <li><a href="#fallback">fallback</a><span>, in §2</span>
   <li><a href="#fallback">fallback size</a><span>, in §2</span>
   <li><a href="#fit-content-block-size">fit-content block size</a><span>, in §2.1</span>
   <li><a href="#fit-content-inline-size">fit-content inline size</a><span>, in §2.1</span>
   <li>
    fit-content(&lt;length-percentage>)
    <ul>
     <li><a href="#valdef-column-width-fit-content-length-percentage">value for column-width</a><span>, in §3.4</span>
     <li><a href="#valdef-width-fit-content-length-percentage">value for width, min-width, max-width, height, min-height, max-height</a><span>, in §3.2</span>
    </ul>
   <li><a href="#fit-content-size">fit-content size</a><span>, in §2.1</span>
   <li>
    height
    <ul>
     <li><a href="#propdef-height">(property)</a><span>, in §3.1.1</span>
     <li><a href="#height">definition of</a><span>, in §3.1.1</span>
    </ul>
   <li><a href="#indefinite">indefinite</a><span>, in §2</span>
   <li><a href="#indefinite">indefinite size</a><span>, in §2</span>
   <li><a href="#inner-size">inner size</a><span>, in §2</span>
   <li><a href="#intrinsic-size">intrinsic size</a><span>, in §2.1</span>
   <li><a href="#constraints">intrinsic size constraint</a><span>, in §2.2</span>
   <li><a href="#intrinsic-size-contribution">intrinsic size contribution</a><span>, in §2.2</span>
   <li><a href="#dfn-intrinsic-sizes">intrinsic sizes</a><span>, in §4.1</span>
   <li><a href="#intrinsic-sizing">Intrinsic sizing</a><span>, in §4</span>
   <li><a href="#valdef-width-length-percentage">&lt;length-percentage></a><span>, in §3.2</span>
   <li>
    max-content
    <ul>
     <li><a href="#max-content">definition of</a><span>, in §2.1</span>
     <li><a href="#valdef-column-width-max-content">value for column-width</a><span>, in §3.4</span>
     <li><a href="#valdef-width-max-content">value for width, min-width, max-width, height, min-height, max-height</a><span>, in §3.2</span>
    </ul>
   <li><a href="#max-content-block-size">max-content block size</a><span>, in §2.1</span>
   <li><a href="#max-content-contribution">max-content block-size contribution</a><span>, in §2.2</span>
   <li><a href="#max-content-constraint">max-content constraint</a><span>, in §2.3</span>
   <li><a href="#max-content-contribution">max-content contribution</a><span>, in §2.2</span>
   <li><a href="#max-content-inline-size">max-content inline size</a><span>, in §2.1</span>
   <li><a href="#max-content-contribution">max-content inline-size contribution</a><span>, in §2.2</span>
   <li><a href="#max-content">max-content size</a><span>, in §2.1</span>
   <li><a href="#propdef-max-height">max-height</a><span>, in §3.1.3</span>
   <li><a href="#max-height">max height</a><span>, in §3.1.3</span>
   <li><a href="#max-height">maximum height</a><span>, in §3.1.3</span>
   <li><a href="#max-width">maximum size</a><span>, in §3.1.3</span>
   <li><a href="#max-width">maximum width</a><span>, in §3.1.3</span>
   <li><a href="#max-width">max size</a><span>, in §3.1.3</span>
   <li><a href="#max-size-properties">max size property</a><span>, in §3.1.2</span>
   <li><a href="#propdef-max-width">max-width</a><span>, in §3.1.3</span>
   <li><a href="#max-width">max width</a><span>, in §3.1.3</span>
   <li>
    min-content
    <ul>
     <li><a href="#min-content">definition of</a><span>, in §2.1</span>
     <li><a href="#valdef-column-width-min-content">value for column-width</a><span>, in §3.4</span>
     <li><a href="#valdef-width-min-content">value for width, min-width, max-width, height, min-height, max-height</a><span>, in §3.2</span>
    </ul>
   <li><a href="#min-content-block-size">min-content block size</a><span>, in §2.1</span>
   <li><a href="#min-content-contribution">min-content block-size contribution</a><span>, in §2.2</span>
   <li><a href="#min-content-constraint">min-content constraint</a><span>, in §2.3</span>
   <li><a href="#min-content-contribution">min-content contribution</a><span>, in §2.2</span>
   <li><a href="#min-content-inline-size">min-content inline size</a><span>, in §2.1</span>
   <li><a href="#min-content-contribution">min-content inline-size contribution</a><span>, in §2.2</span>
   <li><a href="#min-content">min-content size</a><span>, in §2.1</span>
   <li><a href="#propdef-min-height">min-height</a><span>, in §3.1.2</span>
   <li><a href="#min-height">min height</a><span>, in §3.1.2</span>
   <li><a href="#min-height">minimum height</a><span>, in §3.1.2</span>
   <li><a href="#min-width">minimum size</a><span>, in §3.1.2</span>
   <li><a href="#min-width">minimum width</a><span>, in §3.1.2</span>
   <li><a href="#min-width">min size</a><span>, in §3.1.2</span>
   <li><a href="#min-size-properties">min size property</a><span>, in §3.1.1</span>
   <li><a href="#propdef-min-width">min-width</a><span>, in §3.1.2</span>
   <li><a href="#min-width">min width</a><span>, in §3.1.2</span>
   <li><a href="#valdef-max-width-none">none</a><span>, in §3.2</span>
   <li><a href="#outer-size">outer size</a><span>, in §2</span>
   <li><a href="#height">preferred height</a><span>, in §3.1.1</span>
   <li><a href="#preferred-size">preferred size</a><span>, in §3.1.1</span>
   <li><a href="#preferred-size-properties">preferred size property</a><span>, in §3.1</span>
   <li><a href="#width">preferred width</a><span>, in §3.1.1</span>
   <li><a href="#size">size</a><span>, in §2</span>
   <li><a href="#sizing-property">sizing property</a><span>, in §3.1</span>
   <li><a href="#stretch-fit">stretch fit</a><span>, in §2</span>
   <li><a href="#stretch-fit-block-size">stretch-fit block size</a><span>, in §2.1</span>
   <li><a href="#stretch-fit-inline-size">stretch-fit inline size</a><span>, in §2.1</span>
   <li><a href="#stretch-fit-size">stretch-fit size</a><span>, in §2.1</span>
   <li>
    width
    <ul>
     <li><a href="#propdef-width">(property)</a><span>, in §3.1.1</span>
     <li><a href="#width">definition of</a><span>, in §3.1.1</span>
    </ul>
  </ul>
  <aside class="dfn-panel" data-for="term-for-propdef-border">
   <a href="https://drafts.csswg.org/css-backgrounds-3/#propdef-border">https://drafts.csswg.org/css-backgrounds-3/#propdef-border</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-border">3.3. 
Box Edges for Sizing: the box-sizing property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-border-box">
   <a href="https://drafts.csswg.org/css-box-3/#border-box">https://drafts.csswg.org/css-box-3/#border-box</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-border-box">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-border-box①">3.3. 
Box Edges for Sizing: the box-sizing property</a> <a href="#ref-for-border-box②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-content-box">
   <a href="https://drafts.csswg.org/css-box-3/#content-box">https://drafts.csswg.org/css-box-3/#content-box</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-content-box">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-content-box①">3.3. 
Box Edges for Sizing: the box-sizing property</a> <a href="#ref-for-content-box②">(2)</a> <a href="#ref-for-content-box③">(3)</a> <a href="#ref-for-content-box④">(4)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-margin-properties">
   <a href="https://drafts.csswg.org/css-box-3/#margin-properties">https://drafts.csswg.org/css-box-3/#margin-properties</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-margin-properties">5.1. 
	Percentage Sizing</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-padding">
   <a href="https://drafts.csswg.org/css-box-3/#propdef-padding">https://drafts.csswg.org/css-box-3/#propdef-padding</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-padding">3.3. 
Box Edges for Sizing: the box-sizing property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-padding-properties">
   <a href="https://drafts.csswg.org/css-box-3/#padding-properties">https://drafts.csswg.org/css-box-3/#padding-properties</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-padding-properties">5.1. 
	Percentage Sizing</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-computed-value">
   <a href="https://drafts.csswg.org/css-cascade-4/#computed-value">https://drafts.csswg.org/css-cascade-4/#computed-value</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-computed-value">3.3. 
Box Edges for Sizing: the box-sizing property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-initial-value">
   <a href="https://drafts.csswg.org/css-cascade-4/#initial-value">https://drafts.csswg.org/css-cascade-4/#initial-value</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-initial-value">5.1. 
	Percentage Sizing</a> <a href="#ref-for-initial-value①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-block-box">
   <a href="https://drafts.csswg.org/css-display-3/#block-box">https://drafts.csswg.org/css-display-3/#block-box</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-block-box">3.2.2. 
Containing or Excluding Floats</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-block-container">
   <a href="https://drafts.csswg.org/css-display-3/#block-container">https://drafts.csswg.org/css-display-3/#block-container</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-block-container">2.1. 
Auto Box Sizes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-box">
   <a href="https://drafts.csswg.org/css-display-3/#box">https://drafts.csswg.org/css-display-3/#box</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-box">2. 
Terminology</a> <a href="#ref-for-box①">(2)</a>
    <li><a href="#ref-for-box②">3.3. 
Box Edges for Sizing: the box-sizing property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-containing-block">
   <a href="https://drafts.csswg.org/css-display-3/#containing-block">https://drafts.csswg.org/css-display-3/#containing-block</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-containing-block">2. 
Terminology</a> <a href="#ref-for-containing-block①">(2)</a>
    <li><a href="#ref-for-containing-block②">2.2. 
Intrinsic Size Contributions</a> <a href="#ref-for-containing-block③">(2)</a>
    <li><a href="#ref-for-containing-block④">2.3. 
Intrinsic Size Constraints</a> <a href="#ref-for-containing-block⑤">(2)</a>
    <li><a href="#ref-for-containing-block⑥">3.1.1. 
Preferred Size Properties: the width and height properties</a>
    <li><a href="#ref-for-containing-block⑦">3.1.2. 
Minimum Size Properties: the min-width and min-height properties</a>
    <li><a href="#ref-for-containing-block⑧">3.1.3. 
Maximum Size Properties: the max-width and max-height properties</a>
    <li><a href="#ref-for-containing-block⑨">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a> <a href="#ref-for-containing-block①⓪">(2)</a>
    <li><a href="#ref-for-containing-block①①">5.1. 
	Percentage Sizing</a> <a href="#ref-for-containing-block①②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-display">
   <a href="https://drafts.csswg.org/css-display-3/#propdef-display">https://drafts.csswg.org/css-display-3/#propdef-display</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-display">3.2.2. 
Containing or Excluding Floats</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-display-type">
   <a href="https://drafts.csswg.org/css-display-3/#display-type">https://drafts.csswg.org/css-display-3/#display-type</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-display-type">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-formatting-context">
   <a href="https://drafts.csswg.org/css-display-3/#formatting-context">https://drafts.csswg.org/css-display-3/#formatting-context</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-formatting-context">3.2.2. 
Containing or Excluding Floats</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-initial-containing-block">
   <a href="https://drafts.csswg.org/css-display-3/#initial-containing-block">https://drafts.csswg.org/css-display-3/#initial-containing-block</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-initial-containing-block">2. 
Terminology</a> <a href="#ref-for-initial-containing-block①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-inline">
   <a href="https://drafts.csswg.org/css-display-3/#inline">https://drafts.csswg.org/css-display-3/#inline</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-inline">3.1.1. 
Preferred Size Properties: the width and height properties</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-inline-box">
   <a href="https://drafts.csswg.org/css-display-3/#inline-box">https://drafts.csswg.org/css-display-3/#inline-box</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-inline-box">2.1. 
Auto Box Sizes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-non-replaced">
   <a href="https://drafts.csswg.org/css-display-3/#non-replaced">https://drafts.csswg.org/css-display-3/#non-replaced</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-non-replaced">3.1.1. 
Preferred Size Properties: the width and height properties</a>
    <li><a href="#ref-for-non-replaced①">5.1. 
	Percentage Sizing</a> <a href="#ref-for-non-replaced②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-replaced-element">
   <a href="https://drafts.csswg.org/css-display-3/#replaced-element">https://drafts.csswg.org/css-display-3/#replaced-element</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-replaced-element">5.1. 
	Percentage Sizing</a> <a href="#ref-for-replaced-element①">(2)</a> <a href="#ref-for-replaced-element②">(3)</a>
    <li><a href="#ref-for-replaced-element③"> Compressible Replaced Elements</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-replaced-element">
   <a href="https://drafts.csswg.org/css-display-3/#replaced-element">https://drafts.csswg.org/css-display-3/#replaced-element</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-replaced-element">5.1. 
	Percentage Sizing</a> <a href="#ref-for-replaced-element①">(2)</a> <a href="#ref-for-replaced-element②">(3)</a>
    <li><a href="#ref-for-replaced-element③"> Compressible Replaced Elements</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-text-run">
   <a href="https://drafts.csswg.org/css-display-3/#text-run">https://drafts.csswg.org/css-display-3/#text-run</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-text-run">4.1. 
Intrinsic Sizes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-flex-item">
   <a href="https://drafts.csswg.org/css-flexbox-1/#flex-item">https://drafts.csswg.org/css-flexbox-1/#flex-item</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-flex-item">5.1. 
	Percentage Sizing</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-flex-basis">
   <a href="https://drafts.csswg.org/css-flexbox-1/#propdef-flex-basis">https://drafts.csswg.org/css-flexbox-1/#propdef-flex-basis</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-flex-basis">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-propdef-flex-basis①">3.3. 
Box Edges for Sizing: the box-sizing property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-grid-item">
   <a href="https://drafts.csswg.org/css-grid-1/#grid-item">https://drafts.csswg.org/css-grid-1/#grid-item</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-grid-item">5.1. 
	Percentage Sizing</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-block-size">
   <a href="https://drafts.csswg.org/css-logical-1/#propdef-block-size">https://drafts.csswg.org/css-logical-1/#propdef-block-size</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-block-size">5.1. 
	Percentage Sizing</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-max-block-size">
   <a href="https://drafts.csswg.org/css-logical-1/#propdef-max-block-size">https://drafts.csswg.org/css-logical-1/#propdef-max-block-size</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-max-block-size">5.1. 
	Percentage Sizing</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-at-ruledef-page">
   <a href="https://drafts.csswg.org/css-page-3/#at-ruledef-page">https://drafts.csswg.org/css-page-3/#at-ruledef-page</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-at-ruledef-page">3.1. 
Sizing Properties</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-descdef-page-size">
   <a href="https://drafts.csswg.org/css-page-3/#descdef-page-size">https://drafts.csswg.org/css-page-3/#descdef-page-size</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-descdef-page-size">3.1. 
Sizing Properties</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-soft-wrap-opportunity">
   <a href="https://drafts.csswg.org/css-text-3/#soft-wrap-opportunity">https://drafts.csswg.org/css-text-3/#soft-wrap-opportunity</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-soft-wrap-opportunity">4.1. 
Intrinsic Sizes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-length-value">
   <a href="https://drafts.csswg.org/css-values-3/#length-value">https://drafts.csswg.org/css-values-3/#length-value</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-length-value">2. 
Terminology</a>
    <li><a href="#ref-for-length-value①">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a> <a href="#ref-for-length-value②">(2)</a>
    <li><a href="#ref-for-length-value③">3.3. 
Box Edges for Sizing: the box-sizing property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-percentage-value">
   <a href="https://drafts.csswg.org/css-values-3/#percentage-value">https://drafts.csswg.org/css-values-3/#percentage-value</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-percentage-value">2. 
Terminology</a>
    <li><a href="#ref-for-percentage-value①">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a> <a href="#ref-for-percentage-value②">(2)</a>
    <li><a href="#ref-for-percentage-value③">3.3. 
Box Edges for Sizing: the box-sizing property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-typedef-length-percentage">
   <a href="https://drafts.csswg.org/css-values-4/#typedef-length-percentage">https://drafts.csswg.org/css-values-4/#typedef-length-percentage</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-typedef-length-percentage">3.1.1. 
Preferred Size Properties: the width and height properties</a> <a href="#ref-for-typedef-length-percentage①">(2)</a> <a href="#ref-for-typedef-length-percentage②">(3)</a>
    <li><a href="#ref-for-typedef-length-percentage③">3.1.2. 
Minimum Size Properties: the min-width and min-height properties</a> <a href="#ref-for-typedef-length-percentage④">(2)</a> <a href="#ref-for-typedef-length-percentage⑤">(3)</a>
    <li><a href="#ref-for-typedef-length-percentage⑥">3.1.3. 
Maximum Size Properties: the max-width and max-height properties</a> <a href="#ref-for-typedef-length-percentage⑦">(2)</a> <a href="#ref-for-typedef-length-percentage⑧">(3)</a>
    <li><a href="#ref-for-typedef-length-percentage⑨">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a> <a href="#ref-for-typedef-length-percentage①⓪">(2)</a> <a href="#ref-for-typedef-length-percentage①①">(3)</a> <a href="#ref-for-typedef-length-percentage①②">(4)</a>
    <li><a href="#ref-for-typedef-length-percentage①③">3.3. 
Box Edges for Sizing: the box-sizing property</a> <a href="#ref-for-typedef-length-percentage①④">(2)</a> <a href="#ref-for-typedef-length-percentage①⑤">(3)</a> <a href="#ref-for-typedef-length-percentage①⑥">(4)</a>
    <li><a href="#ref-for-typedef-length-percentage①⑦">3.4. 
New Column Sizing Values: the min-content, max-content, and fit-content() values</a> <a href="#ref-for-typedef-length-percentage①⑧">(2)</a> <a href="#ref-for-typedef-length-percentage①⑨">(3)</a> <a href="#ref-for-typedef-length-percentage②⓪">(4)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-css-wide-keywords">
   <a href="https://drafts.csswg.org/css-values-4/#css-wide-keywords">https://drafts.csswg.org/css-values-4/#css-wide-keywords</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-css-wide-keywords">1.2. 
Values</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-comb-one">
   <a href="https://drafts.csswg.org/css-values-4/#comb-one">https://drafts.csswg.org/css-values-4/#comb-one</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-comb-one">3.1.1. 
Preferred Size Properties: the width and height properties</a> <a href="#ref-for-comb-one①">(2)</a> <a href="#ref-for-comb-one②">(3)</a> <a href="#ref-for-comb-one③">(4)</a>
    <li><a href="#ref-for-comb-one④">3.1.2. 
Minimum Size Properties: the min-width and min-height properties</a> <a href="#ref-for-comb-one⑤">(2)</a> <a href="#ref-for-comb-one⑥">(3)</a> <a href="#ref-for-comb-one⑦">(4)</a>
    <li><a href="#ref-for-comb-one⑧">3.1.3. 
Maximum Size Properties: the max-width and max-height properties</a> <a href="#ref-for-comb-one⑨">(2)</a> <a href="#ref-for-comb-one①⓪">(3)</a> <a href="#ref-for-comb-one①①">(4)</a>
    <li><a href="#ref-for-comb-one①②">3.3. 
Box Edges for Sizing: the box-sizing property</a>
    <li><a href="#ref-for-comb-one①③">3.4. 
New Column Sizing Values: the min-content, max-content, and fit-content() values</a> <a href="#ref-for-comb-one①④">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-block-axis">
   <a href="https://drafts.csswg.org/css-writing-modes-4/#block-axis">https://drafts.csswg.org/css-writing-modes-4/#block-axis</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-block-axis">2.1. 
Auto Box Sizes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-block-size">
   <a href="https://drafts.csswg.org/css-writing-modes-4/#block-size">https://drafts.csswg.org/css-writing-modes-4/#block-size</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-block-size">2. 
Terminology</a> <a href="#ref-for-block-size①">(2)</a>
    <li><a href="#ref-for-block-size②">2.1. 
Auto Box Sizes</a>
    <li><a href="#ref-for-block-size③">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a> <a href="#ref-for-block-size④">(2)</a>
    <li><a href="#ref-for-block-size⑤">5.1. 
	Percentage Sizing</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-flow-relative">
   <a href="https://drafts.csswg.org/css-writing-modes-4/#flow-relative">https://drafts.csswg.org/css-writing-modes-4/#flow-relative</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-flow-relative">3.1. 
Sizing Properties</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-inline-axis">
   <a href="https://drafts.csswg.org/css-writing-modes-4/#inline-axis">https://drafts.csswg.org/css-writing-modes-4/#inline-axis</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-inline-axis">2.1. 
Auto Box Sizes</a> <a href="#ref-for-inline-axis①">(2)</a>
    <li><a href="#ref-for-inline-axis②">4.1. 
Intrinsic Sizes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-inline-size">
   <a href="https://drafts.csswg.org/css-writing-modes-4/#inline-size">https://drafts.csswg.org/css-writing-modes-4/#inline-size</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-inline-size">2. 
Terminology</a> <a href="#ref-for-inline-size①">(2)</a>
    <li><a href="#ref-for-inline-size②">2.1. 
Auto Box Sizes</a> <a href="#ref-for-inline-size③">(2)</a> <a href="#ref-for-inline-size④">(3)</a> <a href="#ref-for-inline-size⑤">(4)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-physical">
   <a href="https://drafts.csswg.org/css-writing-modes-4/#physical">https://drafts.csswg.org/css-writing-modes-4/#physical</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-physical">3.1.1. 
Preferred Size Properties: the width and height properties</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-vertical-writing-mode">
   <a href="https://drafts.csswg.org/css-writing-modes-4/#vertical-writing-mode">https://drafts.csswg.org/css-writing-modes-4/#vertical-writing-mode</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-vertical-writing-mode">4.1. 
Intrinsic Sizes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-writing-mode">
   <a href="https://drafts.csswg.org/css-writing-modes-4/#writing-mode">https://drafts.csswg.org/css-writing-modes-4/#writing-mode</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-writing-mode">2. 
Terminology</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-propdef-column-width">
   <a href="https://drafts.csswg.org/css-multicol-1/#propdef-column-width">https://drafts.csswg.org/css-multicol-1/#propdef-column-width</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-column-width">1.1. 
Module interactions</a>
    <li><a href="#ref-for-propdef-column-width①">3.4. 
New Column Sizing Values: the min-content, max-content, and fit-content() values</a> <a href="#ref-for-propdef-column-width②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-dom-window-getcomputedstyle">
   <a href="https://drafts.csswg.org/cssom-1/#dom-window-getcomputedstyle">https://drafts.csswg.org/cssom-1/#dom-window-getcomputedstyle</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-dom-window-getcomputedstyle">3.3. 
Box Edges for Sizing: the box-sizing property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-resolved-value">
   <a href="https://drafts.csswg.org/cssom-1/#resolved-value">https://drafts.csswg.org/cssom-1/#resolved-value</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-resolved-value">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-the-button-element">
   <a href="https://html.spec.whatwg.org/multipage/form-elements.html#the-button-element">https://html.spec.whatwg.org/multipage/form-elements.html#the-button-element</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-the-button-element">3.3. 
Box Edges for Sizing: the box-sizing property</a>
    <li><a href="#ref-for-the-button-element①"> Compressible Replaced Elements</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-the-iframe-element">
   <a href="https://html.spec.whatwg.org/multipage/iframe-embed-object.html#the-iframe-element">https://html.spec.whatwg.org/multipage/iframe-embed-object.html#the-iframe-element</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-the-iframe-element">4.1. 
Intrinsic Sizes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-the-input-element">
   <a href="https://html.spec.whatwg.org/multipage/input.html#the-input-element">https://html.spec.whatwg.org/multipage/input.html#the-input-element</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-the-input-element">4.1. 
Intrinsic Sizes</a>
    <li><a href="#ref-for-the-input-element①">5.1. 
	Percentage Sizing</a>
    <li><a href="#ref-for-the-input-element②"> Compressible Replaced Elements</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-the-meter-element">
   <a href="https://html.spec.whatwg.org/multipage/form-elements.html#the-meter-element">https://html.spec.whatwg.org/multipage/form-elements.html#the-meter-element</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-the-meter-element"> Compressible Replaced Elements</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-the-progress-element">
   <a href="https://html.spec.whatwg.org/multipage/form-elements.html#the-progress-element">https://html.spec.whatwg.org/multipage/form-elements.html#the-progress-element</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-the-progress-element"> Compressible Replaced Elements</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-textarea-raw-value">
   <a href="https://html.spec.whatwg.org/multipage/form-elements.html#concept-textarea-raw-value">https://html.spec.whatwg.org/multipage/form-elements.html#concept-textarea-raw-value</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-textarea-raw-value">4.1. 
Intrinsic Sizes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-the-select-element">
   <a href="https://html.spec.whatwg.org/multipage/form-elements.html#the-select-element">https://html.spec.whatwg.org/multipage/form-elements.html#the-select-element</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-the-select-element">5.1. 
	Percentage Sizing</a>
    <li><a href="#ref-for-the-select-element①"> Compressible Replaced Elements</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-the-textarea-element">
   <a href="https://html.spec.whatwg.org/multipage/form-elements.html#the-textarea-element">https://html.spec.whatwg.org/multipage/form-elements.html#the-textarea-element</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-the-textarea-element">4.1. 
Intrinsic Sizes</a>
    <li><a href="#ref-for-the-textarea-element①"> Compressible Replaced Elements</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-attr-input-type">
   <a href="https://html.spec.whatwg.org/multipage/input.html#attr-input-type">https://html.spec.whatwg.org/multipage/input.html#attr-input-type</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-attr-input-type"> Compressible Replaced Elements</a>
   </ul>
  </aside>
  <h3 class="no-num no-ref heading settled" id="index-defined-elsewhere"><span class="content">Terms defined by reference</span><a class="self-link" href="#index-defined-elsewhere"></a></h3>
  <ul class="index">
   <li>
    <a data-link-type="biblio">[css-backgrounds-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-propdef-border" style="color:initial">border</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-box-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-border-box" style="color:initial">border box</span>
     <li><span class="dfn-paneled" id="term-for-content-box" style="color:initial">content box</span>
     <li><span class="dfn-paneled" id="term-for-margin-properties" style="color:initial">margin properties</span>
     <li><span class="dfn-paneled" id="term-for-propdef-padding" style="color:initial">padding</span>
     <li><span class="dfn-paneled" id="term-for-padding-properties" style="color:initial">padding properties</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-cascade-4]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-computed-value" style="color:initial">computed value</span>
     <li><span class="dfn-paneled" id="term-for-initial-value" style="color:initial">initial value</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-display-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-block-box" style="color:initial">block box</span>
     <li><span class="dfn-paneled" id="term-for-block-container" style="color:initial">block container</span>
     <li><span class="dfn-paneled" id="term-for-box" style="color:initial">box</span>
     <li><span class="dfn-paneled" id="term-for-containing-block" style="color:initial">containing block</span>
     <li><span class="dfn-paneled" id="term-for-propdef-display" style="color:initial">display</span>
     <li><span class="dfn-paneled" id="term-for-display-type" style="color:initial">display type</span>
     <li><span class="dfn-paneled" id="term-for-formatting-context" style="color:initial">formatting context</span>
     <li><span class="dfn-paneled" id="term-for-initial-containing-block" style="color:initial">initial containing block</span>
     <li><span class="dfn-paneled" id="term-for-inline" style="color:initial">inline</span>
     <li><span class="dfn-paneled" id="term-for-inline-box" style="color:initial">inline box</span>
     <li><span class="dfn-paneled" id="term-for-non-replaced" style="color:initial">non-replaced</span>
     <li><span class="dfn-paneled" id="term-for-replaced-element" style="color:initial">replaced</span>
     <li><span class="dfn-paneled" id="term-for-replaced-element①" style="color:initial">replaced element</span>
     <li><span class="dfn-paneled" id="term-for-text-run" style="color:initial">text run</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-flexbox-1]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-flex-item" style="color:initial">flex item</span>
     <li><span class="dfn-paneled" id="term-for-propdef-flex-basis" style="color:initial">flex-basis</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-grid-1]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-grid-item" style="color:initial">grid item</span>
    </ul>
   <li>
    <a data-link-type="biblio">[CSS-LOGICAL-1]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-propdef-block-size" style="color:initial">block-size</span>
     <li><span class="dfn-paneled" id="term-for-propdef-max-block-size" style="color:initial">max-block-size</span>
    </ul>
   <li>
    <a data-link-type="biblio">[CSS-PAGE-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-at-ruledef-page" style="color:initial">@page</span>
     <li><span class="dfn-paneled" id="term-for-descdef-page-size" style="color:initial">size</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-text-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-soft-wrap-opportunity" style="color:initial">soft wrap opportunity</span>
    </ul>
   <li>
    <a data-link-type="biblio">[CSS-VALUES-3]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-length-value" style="color:initial">&lt;length></span>
     <li><span class="dfn-paneled" id="term-for-percentage-value" style="color:initial">&lt;percentage></span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-values-4]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-typedef-length-percentage" style="color:initial">&lt;length-percentage></span>
     <li><span class="dfn-paneled" id="term-for-css-wide-keywords" style="color:initial">css-wide keywords</span>
     <li><span class="dfn-paneled" id="term-for-comb-one" style="color:initial">|</span>
    </ul>
   <li>
    <a data-link-type="biblio">[css-writing-modes-4]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-block-axis" style="color:initial">block axis</span>
     <li><span class="dfn-paneled" id="term-for-block-size" style="color:initial">block size</span>
     <li><span class="dfn-paneled" id="term-for-flow-relative" style="color:initial">flow-relative</span>
     <li><span class="dfn-paneled" id="term-for-inline-axis" style="color:initial">inline axis</span>
     <li><span class="dfn-paneled" id="term-for-inline-size" style="color:initial">inline size</span>
     <li><span class="dfn-paneled" id="term-for-physical" style="color:initial">physical</span>
     <li><span class="dfn-paneled" id="term-for-vertical-writing-mode" style="color:initial">vertical writing mode</span>
     <li><span class="dfn-paneled" id="term-for-writing-mode" style="color:initial">writing mode</span>
    </ul>
   <li>
    <a data-link-type="biblio">[CSS3COL]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-propdef-column-width" style="color:initial">column-width</span>
    </ul>
   <li>
    <a data-link-type="biblio">[cssom-1]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-dom-window-getcomputedstyle" style="color:initial">getComputedStyle(elt)</span>
     <li><span class="dfn-paneled" id="term-for-resolved-value" style="color:initial">resolved value</span>
    </ul>
   <li>
    <a data-link-type="biblio">[HTML]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-the-button-element" style="color:initial">button</span>
     <li><span class="dfn-paneled" id="term-for-the-iframe-element" style="color:initial">iframe</span>
     <li><span class="dfn-paneled" id="term-for-the-input-element" style="color:initial">input</span>
     <li><span class="dfn-paneled" id="term-for-the-meter-element" style="color:initial">meter</span>
     <li><span class="dfn-paneled" id="term-for-the-progress-element" style="color:initial">progress</span>
     <li><span class="dfn-paneled" id="term-for-concept-textarea-raw-value" style="color:initial">raw value</span>
     <li><span class="dfn-paneled" id="term-for-the-select-element" style="color:initial">select</span>
     <li><span class="dfn-paneled" id="term-for-the-textarea-element" style="color:initial">textarea</span>
     <li><span class="dfn-paneled" id="term-for-attr-input-type" style="color:initial">type</span>
    </ul>
  </ul>
  <h2 class="no-num no-ref heading settled" id="references"><span class="content">References</span><a class="self-link" href="#references"></a></h2>
  <h3 class="no-num no-ref heading settled" id="normative"><span class="content">Normative References</span><a class="self-link" href="#normative"></a></h3>
  <dl>
   <dt id="biblio-css-box-3">[CSS-BOX-3]
   <dd>Elika Etemad. <a href="https://www.w3.org/TR/css-box-3/">CSS Box Model Module Level 3</a>. 18 December 2018. WD. URL: <a href="https://www.w3.org/TR/css-box-3/">https://www.w3.org/TR/css-box-3/</a>
   <dt id="biblio-css-cascade-4">[CSS-CASCADE-4]
   <dd>Elika Etemad; Tab Atkins Jr.. <a href="https://www.w3.org/TR/css-cascade-4/">CSS Cascading and Inheritance Level 4</a>. 28 August 2018. CR. URL: <a href="https://www.w3.org/TR/css-cascade-4/">https://www.w3.org/TR/css-cascade-4/</a>
   <dt id="biblio-css-display-3">[CSS-DISPLAY-3]
   <dd>Tab Atkins Jr.; Elika Etemad. <a href="https://www.w3.org/TR/css-display-3/">CSS Display Module Level 3</a>. 28 August 2018. CR. URL: <a href="https://www.w3.org/TR/css-display-3/">https://www.w3.org/TR/css-display-3/</a>
   <dt id="biblio-css-flexbox-1">[CSS-FLEXBOX-1]
   <dd>Tab Atkins Jr.; et al. <a href="https://www.w3.org/TR/css-flexbox-1/">CSS Flexible Box Layout Module Level 1</a>. 19 November 2018. CR. URL: <a href="https://www.w3.org/TR/css-flexbox-1/">https://www.w3.org/TR/css-flexbox-1/</a>
   <dt id="biblio-css-logical-1">[CSS-LOGICAL-1]
   <dd>Rossen Atanassov; Elika Etemad. <a href="https://www.w3.org/TR/css-logical-1/">CSS Logical Properties and Values Level 1</a>. 27 August 2018. WD. URL: <a href="https://www.w3.org/TR/css-logical-1/">https://www.w3.org/TR/css-logical-1/</a>
   <dt id="biblio-css-page-3">[CSS-PAGE-3]
   <dd>Elika Etemad; Simon Sapin. <a href="https://www.w3.org/TR/css-page-3/">CSS Paged Media Module Level 3</a>. 18 October 2018. WD. URL: <a href="https://www.w3.org/TR/css-page-3/">https://www.w3.org/TR/css-page-3/</a>
   <dt id="biblio-css-text-3">[CSS-TEXT-3]
   <dd>Elika Etemad; Koji Ishii; Florian Rivoal. <a href="https://www.w3.org/TR/css-text-3/">CSS Text Module Level 3</a>. 12 December 2018. WD. URL: <a href="https://www.w3.org/TR/css-text-3/">https://www.w3.org/TR/css-text-3/</a>
   <dt id="biblio-css-values-3">[CSS-VALUES-3]
   <dd>Tab Atkins Jr.; Elika Etemad. <a href="https://www.w3.org/TR/css-values-3/">CSS Values and Units Module Level 3</a>. 31 January 2019. CR. URL: <a href="https://www.w3.org/TR/css-values-3/">https://www.w3.org/TR/css-values-3/</a>
   <dt id="biblio-css-values-4">[CSS-VALUES-4]
   <dd>Tab Atkins Jr.; Elika Etemad. <a href="https://www.w3.org/TR/css-values-4/">CSS Values and Units Module Level 4</a>. 31 January 2019. WD. URL: <a href="https://www.w3.org/TR/css-values-4/">https://www.w3.org/TR/css-values-4/</a>
   <dt id="biblio-css-writing-modes-4">[CSS-WRITING-MODES-4]
   <dd>Elika Etemad; Koji Ishii. <a href="https://www.w3.org/TR/css-writing-modes-4/">CSS Writing Modes Level 4</a>. 24 May 2018. CR. URL: <a href="https://www.w3.org/TR/css-writing-modes-4/">https://www.w3.org/TR/css-writing-modes-4/</a>
   <dt id="biblio-css2">[CSS2]
   <dd>Bert Bos; et al. <a href="https://www.w3.org/TR/CSS2/">Cascading Style Sheets Level 2 Revision 1 (CSS 2.1) Specification</a>. 7 June 2011. REC. URL: <a href="https://www.w3.org/TR/CSS2/">https://www.w3.org/TR/CSS2/</a>
   <dt id="biblio-css3col">[CSS3COL]
   <dd>Florian Rivoal; Rachel Andrew. <a href="https://www.w3.org/TR/css-multicol-1/">CSS Multi-column Layout Module Level 1</a>. 28 May 2018. WD. URL: <a href="https://www.w3.org/TR/css-multicol-1/">https://www.w3.org/TR/css-multicol-1/</a>
   <dt id="biblio-cssom-1">[CSSOM-1]
   <dd>Simon Pieters; Glenn Adams. <a href="https://www.w3.org/TR/cssom-1/">CSS Object Model (CSSOM)</a>. 17 March 2016. WD. URL: <a href="https://www.w3.org/TR/cssom-1/">https://www.w3.org/TR/cssom-1/</a>
   <dt id="biblio-html">[HTML]
   <dd>Anne van Kesteren; et al. <a href="https://html.spec.whatwg.org/multipage/">HTML Standard</a>. Living Standard. URL: <a href="https://html.spec.whatwg.org/multipage/">https://html.spec.whatwg.org/multipage/</a>
   <dt id="biblio-rfc2119">[RFC2119]
   <dd>S. Bradner. <a href="https://tools.ietf.org/html/rfc2119">Key words for use in RFCs to Indicate Requirement Levels</a>. March 1997. Best Current Practice. URL: <a href="https://tools.ietf.org/html/rfc2119">https://tools.ietf.org/html/rfc2119</a>
  </dl>
  <h3 class="no-num no-ref heading settled" id="informative"><span class="content">Informative References</span><a class="self-link" href="#informative"></a></h3>
  <dl>
   <dt id="biblio-css-backgrounds-3">[CSS-BACKGROUNDS-3]
   <dd>Bert Bos; Elika Etemad; Brad Kemper. <a href="https://www.w3.org/TR/css-backgrounds-3/">CSS Backgrounds and Borders Module Level 3</a>. 17 October 2017. CR. URL: <a href="https://www.w3.org/TR/css-backgrounds-3/">https://www.w3.org/TR/css-backgrounds-3/</a>
   <dt id="biblio-css-grid-1">[CSS-GRID-1]
   <dd>Tab Atkins Jr.; Elika Etemad; Rossen Atanassov. <a href="https://www.w3.org/TR/css-grid-1/">CSS Grid Layout Module Level 1</a>. 14 December 2017. CR. URL: <a href="https://www.w3.org/TR/css-grid-1/">https://www.w3.org/TR/css-grid-1/</a>
   <dt id="biblio-css-ui-3">[CSS-UI-3]
   <dd>Tantek Çelik; Florian Rivoal. <a href="https://www.w3.org/TR/css-ui-3/">CSS Basic User Interface Module Level 3 (CSS3 UI)</a>. 21 June 2018. REC. URL: <a href="https://www.w3.org/TR/css-ui-3/">https://www.w3.org/TR/css-ui-3/</a>
  </dl>
  <h2 class="no-num no-ref heading settled" id="property-index"><span class="content">Property Index</span><a class="self-link" href="#property-index"></a></h2>
  <div class="big-element-wrapper">
   <table class="index">
    <thead>
     <tr>
      <th scope="col">Name
      <th scope="col">Value
      <th scope="col">Initial
      <th scope="col">Applies to
      <th scope="col">Inh.
      <th scope="col">%ages
      <th scope="col">Ani­mat­able
      <th scope="col">Anim­ation type
      <th scope="col">Canonical order
      <th scope="col">Com­puted value
    <tbody>
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-box-sizing" id="ref-for-propdef-box-sizing⑨">box-sizing</a>
      <td>content-box | border-box
      <td>content-box
      <td>all elements that accept width or height
      <td>no
      <td>N/A
      <td>
      <td>discrete
      <td>per grammar
      <td>specified keyword
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-height" id="ref-for-propdef-height②⑤">height</a>
      <td>auto | &lt;length-percentage> | min-content | max-content | fit-content(&lt;length-percentage>)
      <td>auto
      <td>all elements except non-replaced inlines
      <td>no
      <td>relative to width/height of containing block
      <td>
      <td>by computed value type, recursing into fit-content()
      <td>per grammar
      <td>as specified, with &lt;length-percentage> values computed
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-max-height" id="ref-for-propdef-max-height⑧">max-height</a>
      <td>none | &lt;length-percentage> | min-content | max-content | fit-content(&lt;length-percentage>)
      <td>none
      <td>all elements that accept width or height
      <td>no
      <td>relative to width/height of containing block
      <td>by computed value, recursing into fit-content()
      <td>
      <td>per grammar
      <td>as specified, with &lt;length-percentage> values computed
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-max-width" id="ref-for-propdef-max-width⑧">max-width</a>
      <td>none | &lt;length-percentage> | min-content | max-content | fit-content(&lt;length-percentage>)
      <td>none
      <td>all elements that accept width or height
      <td>no
      <td>relative to width/height of containing block
      <td>by computed value, recursing into fit-content()
      <td>
      <td>per grammar
      <td>as specified, with &lt;length-percentage> values computed
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-min-height" id="ref-for-propdef-min-height①①">min-height</a>
      <td>auto | &lt;length-percentage> | min-content | max-content | fit-content(&lt;length-percentage>)
      <td>auto
      <td>all elements that accept width or height
      <td>no
      <td>relative to width/height of containing block
      <td>by computed value, recursing into fit-content()
      <td>
      <td>per grammar
      <td>as specified, with &lt;length-percentage> values computed
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-min-width" id="ref-for-propdef-min-width⑧">min-width</a>
      <td>auto | &lt;length-percentage> | min-content | max-content | fit-content(&lt;length-percentage>)
      <td>auto
      <td>all elements that accept width or height
      <td>no
      <td>relative to width/height of containing block
      <td>by computed value, recursing into fit-content()
      <td>
      <td>per grammar
      <td>as specified, with &lt;length-percentage> values computed
     <tr>
      <th scope="row"><a class="css" data-link-type="property" href="#propdef-width" id="ref-for-propdef-width②⑥">width</a>
      <td>auto | &lt;length-percentage> | min-content | max-content | fit-content(&lt;length-percentage>)
      <td>auto
      <td>all elements except non-replaced inlines
      <td>no
      <td>relative to width/height of containing block
      <td>
      <td>by computed value type, recursing into fit-content()
      <td>per grammar
      <td>as specified, with &lt;length-percentage> values computed
   </table>
  </div>
  <h2 class="no-num no-ref heading settled" id="issues-index"><span class="content">Issues Index</span><a class="self-link" href="#issues-index"></a></h2>
  <div style="counter-reset:issue">
   <div class="issue"> This spec needs illustrations! See <a href="https://github.com/w3c/csswg-drafts/issues/1938">issue</a>.<a href="#issue-664b2cc3"> ↵ </a></div>
   <div class="issue"> We would like to define shorthands for each pair of sizing properties
	(e.g. <a class="property" data-link-type="propdesc" href="#propdef-width">width</a> and <a class="property" data-link-type="propdesc" href="#propdef-height">height</a>)
	but there is a naming conflict with the <a class="css" data-link-type="maybe" href="https://drafts.csswg.org/css-page-3/#at-ruledef-page">@page</a> <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-page-3/#descdef-page-size">size</a> descriptor <a data-link-type="biblio" href="#biblio-css-page-3">[CSS-PAGE-3]</a>,
	so this has been deferred to Level 4.
	Suggestions on how to resolve this problem are welcome,
	see <a href="https://github.com/w3c/csswg-drafts/issues/820">discussion</a>.<a href="#issue-6eb2c542"> ↵ </a></div>
   <div class="issue"> Replace this section with references to the new term <a data-link-type="dfn" href="#automatic-size">automatic size</a>.<a href="#issue-6215c343"> ↵ </a></div>
   <div class="issue"> Letting percentages still resolve against a definite <a class="property" data-link-type="propdesc" href="#propdef-height">height</a> when the min-height is intrinsic is an open issue.
		(CSS2 has a general statement about "height depending on contents",
		which this technically is,
		even though CSS2 didn’t have content-dependent keywords for <a class="property" data-link-type="propdesc" href="#propdef-min-height">min-height</a>.
		Since this is new, we think we could have this different behavior.)<a href="#issue-9b3707fe"> ↵ </a></div>
  </div>
  <aside class="dfn-panel" data-for="size">
   <b><a href="#size">#size</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-size">2.1. 
Auto Box Sizes</a> <a href="#ref-for-size①">(2)</a> <a href="#ref-for-size②">(3)</a> <a href="#ref-for-size③">(4)</a> <a href="#ref-for-size④">(5)</a> <a href="#ref-for-size⑤">(6)</a> <a href="#ref-for-size⑥">(7)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="inner-size">
   <b><a href="#inner-size">#inner-size</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-inner-size">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-inner-size①">3.3. 
Box Edges for Sizing: the box-sizing property</a> <a href="#ref-for-inner-size②">(2)</a> <a href="#ref-for-inner-size③">(3)</a> <a href="#ref-for-inner-size④">(4)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="outer-size">
   <b><a href="#outer-size">#outer-size</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-outer-size">2.1. 
Auto Box Sizes</a>
    <li><a href="#ref-for-outer-size①">2.2. 
Intrinsic Size Contributions</a>
    <li><a href="#ref-for-outer-size②">3.3. 
Box Edges for Sizing: the box-sizing property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="definite">
   <b><a href="#definite">#definite</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-definite">2. 
Terminology</a> <a href="#ref-for-definite①">(2)</a> <a href="#ref-for-definite②">(3)</a> <a href="#ref-for-definite③">(4)</a>
    <li><a href="#ref-for-definite④">2.1. 
Auto Box Sizes</a> <a href="#ref-for-definite⑤">(2)</a>
    <li><a href="#ref-for-definite⑥">4.1. 
Intrinsic Sizes</a> <a href="#ref-for-definite⑦">(2)</a> <a href="#ref-for-definite⑧">(3)</a> <a href="#ref-for-definite⑨">(4)</a>
    <li><a href="#ref-for-definite①⓪">5.1. 
	Percentage Sizing</a> <a href="#ref-for-definite①①">(2)</a> <a href="#ref-for-definite①②">(3)</a> <a href="#ref-for-definite①③">(4)</a> <a href="#ref-for-definite①④">(5)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="indefinite">
   <b><a href="#indefinite">#indefinite</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-indefinite">2. 
Terminology</a> <a href="#ref-for-indefinite①">(2)</a>
    <li><a href="#ref-for-indefinite②">2.1. 
Auto Box Sizes</a> <a href="#ref-for-indefinite③">(2)</a>
    <li><a href="#ref-for-indefinite④">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-indefinite⑤">3.2.1. 
“Behaving as auto”</a>
    <li><a href="#ref-for-indefinite⑥"> Changes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="available">
   <b><a href="#available">#available</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-available">2. 
Terminology</a> <a href="#ref-for-available①">(2)</a>
    <li><a href="#ref-for-available②">2.1. 
Auto Box Sizes</a> <a href="#ref-for-available③">(2)</a> <a href="#ref-for-available④">(3)</a> <a href="#ref-for-available⑤">(4)</a> <a href="#ref-for-available⑥">(5)</a>
    <li><a href="#ref-for-available⑦">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a> <a href="#ref-for-available⑧">(2)</a>
    <li><a href="#ref-for-available⑨">4.1. 
Intrinsic Sizes</a> <a href="#ref-for-available①⓪">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="stretch-fit">
   <b><a href="#stretch-fit">#stretch-fit</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-stretch-fit">2. 
Terminology</a>
    <li><a href="#ref-for-stretch-fit①">2.1. 
Auto Box Sizes</a>
    <li><a href="#ref-for-stretch-fit②">4.1. 
Intrinsic Sizes</a> <a href="#ref-for-stretch-fit③">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="fallback">
   <b><a href="#fallback">#fallback</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-fallback">2. 
Terminology</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="stretch-fit-size">
   <b><a href="#stretch-fit-size">#stretch-fit-size</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-stretch-fit-size">2.1. 
Auto Box Sizes</a>
    <li><a href="#ref-for-stretch-fit-size①">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="max-content">
   <b><a href="#max-content">#max-content</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-max-content">2.1. 
Auto Box Sizes</a> <a href="#ref-for-max-content①">(2)</a> <a href="#ref-for-max-content②">(3)</a>
    <li><a href="#ref-for-max-content③">2.2. 
Intrinsic Size Contributions</a>
    <li><a href="#ref-for-max-content④">3.4. 
New Column Sizing Values: the min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-max-content⑤">4.1. 
Intrinsic Sizes</a> <a href="#ref-for-max-content⑥">(2)</a> <a href="#ref-for-max-content⑦">(3)</a> <a href="#ref-for-max-content⑧">(4)</a> <a href="#ref-for-max-content⑨">(5)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="max-content-inline-size">
   <b><a href="#max-content-inline-size">#max-content-inline-size</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-max-content-inline-size">3.4. 
New Column Sizing Values: the min-content, max-content, and fit-content() values</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="max-content-block-size">
   <b><a href="#max-content-block-size">#max-content-block-size</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-max-content-block-size">2.1. 
Auto Box Sizes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="min-content">
   <b><a href="#min-content">#min-content</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-min-content">2.1. 
Auto Box Sizes</a> <a href="#ref-for-min-content①">(2)</a>
    <li><a href="#ref-for-min-content②">2.2. 
Intrinsic Size Contributions</a>
    <li><a href="#ref-for-min-content③">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a> <a href="#ref-for-min-content④">(2)</a>
    <li><a href="#ref-for-min-content⑤">3.4. 
New Column Sizing Values: the min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-min-content⑥">4.1. 
Intrinsic Sizes</a> <a href="#ref-for-min-content⑦">(2)</a> <a href="#ref-for-min-content⑧">(3)</a>
    <li><a href="#ref-for-min-content⑨"> Compressible Replaced Elements</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="min-content-inline-size">
   <b><a href="#min-content-inline-size">#min-content-inline-size</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-min-content-inline-size">3.4. 
New Column Sizing Values: the min-content, max-content, and fit-content() values</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="fit-content-size">
   <b><a href="#fit-content-size">#fit-content-size</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-fit-content-size">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="max-content-contribution">
   <b><a href="#max-content-contribution">#max-content-contribution</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-max-content-contribution">2.2. 
Intrinsic Size Contributions</a>
    <li><a href="#ref-for-max-content-contribution①">2.3. 
Intrinsic Size Constraints</a>
    <li><a href="#ref-for-max-content-contribution②">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-max-content-contribution③">4.2. 
Intrinsic Contributions</a>
    <li><a href="#ref-for-max-content-contribution④">5.1. 
	Percentage Sizing</a> <a href="#ref-for-max-content-contribution⑤">(2)</a> <a href="#ref-for-max-content-contribution⑥">(3)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="min-content-contribution">
   <b><a href="#min-content-contribution">#min-content-contribution</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-min-content-contribution">2.2. 
Intrinsic Size Contributions</a>
    <li><a href="#ref-for-min-content-contribution①">2.3. 
Intrinsic Size Constraints</a>
    <li><a href="#ref-for-min-content-contribution②">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-min-content-contribution③">4.2. 
Intrinsic Contributions</a>
    <li><a href="#ref-for-min-content-contribution④">5.1. 
	Percentage Sizing</a> <a href="#ref-for-min-content-contribution⑤">(2)</a> <a href="#ref-for-min-content-contribution⑥">(3)</a> <a href="#ref-for-min-content-contribution⑦">(4)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="intrinsic-size-contribution">
   <b><a href="#intrinsic-size-contribution">#intrinsic-size-contribution</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-intrinsic-size-contribution">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-intrinsic-size-contribution①">5.1. 
	Percentage Sizing</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="max-content-constraint">
   <b><a href="#max-content-constraint">#max-content-constraint</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-max-content-constraint">2. 
Terminology</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="min-content-constraint">
   <b><a href="#min-content-constraint">#min-content-constraint</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-min-content-constraint">2. 
Terminology</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="sizing-property">
   <b><a href="#sizing-property">#sizing-property</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-sizing-property">3.3. 
Box Edges for Sizing: the box-sizing property</a> <a href="#ref-for-sizing-property①">(2)</a> <a href="#ref-for-sizing-property②">(3)</a> <a href="#ref-for-sizing-property③">(4)</a>
    <li><a href="#ref-for-sizing-property④">4.1. 
Intrinsic Sizes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="preferred-size-properties">
   <b><a href="#preferred-size-properties">#preferred-size-properties</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-preferred-size-properties">5.1. 
	Percentage Sizing</a> <a href="#ref-for-preferred-size-properties①">(2)</a> <a href="#ref-for-preferred-size-properties②">(3)</a> <a href="#ref-for-preferred-size-properties③">(4)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-width">
   <b><a href="#propdef-width">#propdef-width</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-width">1. 
Introduction</a>
    <li><a href="#ref-for-propdef-width①">1.1. 
Module interactions</a>
    <li><a href="#ref-for-propdef-width②">3.1. 
Sizing Properties</a> <a href="#ref-for-propdef-width③">(2)</a>
    <li><a href="#ref-for-propdef-width④">3.1.1. 
Preferred Size Properties: the width and height properties</a> <a href="#ref-for-propdef-width⑤">(2)</a>
    <li><a href="#ref-for-propdef-width⑥">3.1.2. 
Minimum Size Properties: the min-width and min-height properties</a>
    <li><a href="#ref-for-propdef-width⑦">3.1.3. 
Maximum Size Properties: the max-width and max-height properties</a>
    <li><a href="#ref-for-propdef-width⑧">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a> <a href="#ref-for-propdef-width⑨">(2)</a>
    <li><a href="#ref-for-propdef-width①⓪">3.2.1. 
“Behaving as auto”</a> <a href="#ref-for-propdef-width①①">(2)</a>
    <li><a href="#ref-for-propdef-width①②">3.3. 
Box Edges for Sizing: the box-sizing property</a> <a href="#ref-for-propdef-width①③">(2)</a> <a href="#ref-for-propdef-width①④">(3)</a> <a href="#ref-for-propdef-width①⑤">(4)</a>
    <li><a href="#ref-for-propdef-width①⑥">4.1. 
Intrinsic Sizes</a> <a href="#ref-for-propdef-width①⑦">(2)</a>
    <li><a href="#ref-for-propdef-width①⑧">5.1. 
	Percentage Sizing</a> <a href="#ref-for-propdef-width①⑨">(2)</a> <a href="#ref-for-propdef-width②⓪">(3)</a> <a href="#ref-for-propdef-width②①">(4)</a> <a href="#ref-for-propdef-width②②">(5)</a> <a href="#ref-for-propdef-width②③">(6)</a>
    <li><a href="#ref-for-propdef-width②④"> Compressible Replaced Elements</a>
    <li><a href="#ref-for-propdef-width②⑤"> Changes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-height">
   <b><a href="#propdef-height">#propdef-height</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-height">1. 
Introduction</a>
    <li><a href="#ref-for-propdef-height①">1.1. 
Module interactions</a>
    <li><a href="#ref-for-propdef-height②">3.1. 
Sizing Properties</a> <a href="#ref-for-propdef-height③">(2)</a>
    <li><a href="#ref-for-propdef-height④">3.1.1. 
Preferred Size Properties: the width and height properties</a> <a href="#ref-for-propdef-height⑤">(2)</a>
    <li><a href="#ref-for-propdef-height⑥">3.1.2. 
Minimum Size Properties: the min-width and min-height properties</a>
    <li><a href="#ref-for-propdef-height⑦">3.1.3. 
Maximum Size Properties: the max-width and max-height properties</a>
    <li><a href="#ref-for-propdef-height⑧">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-propdef-height⑨">3.2.1. 
“Behaving as auto”</a> <a href="#ref-for-propdef-height①⓪">(2)</a>
    <li><a href="#ref-for-propdef-height①①">3.3. 
Box Edges for Sizing: the box-sizing property</a> <a href="#ref-for-propdef-height①②">(2)</a> <a href="#ref-for-propdef-height①③">(3)</a>
    <li><a href="#ref-for-propdef-height①④">4.1. 
Intrinsic Sizes</a> <a href="#ref-for-propdef-height①⑤">(2)</a>
    <li><a href="#ref-for-propdef-height①⑥">5.1. 
	Percentage Sizing</a> <a href="#ref-for-propdef-height①⑦">(2)</a> <a href="#ref-for-propdef-height①⑧">(3)</a> <a href="#ref-for-propdef-height①⑨">(4)</a> <a href="#ref-for-propdef-height②⓪">(5)</a> <a href="#ref-for-propdef-height②①">(6)</a> <a href="#ref-for-propdef-height②②">(7)</a>
    <li><a href="#ref-for-propdef-height②③"> Compressible Replaced Elements</a>
    <li><a href="#ref-for-propdef-height②④"> Changes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="width">
   <b><a href="#width">#width</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-width">2. 
Terminology</a>
    <li><a href="#ref-for-width①">3.3. 
Box Edges for Sizing: the box-sizing property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="height">
   <b><a href="#height">#height</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-height">2. 
Terminology</a>
    <li><a href="#ref-for-height①">3.3. 
Box Edges for Sizing: the box-sizing property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="min-size-properties">
   <b><a href="#min-size-properties">#min-size-properties</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-min-size-properties">5.1. 
	Percentage Sizing</a> <a href="#ref-for-min-size-properties①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-min-width">
   <b><a href="#propdef-min-width">#propdef-min-width</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-min-width">1.1. 
Module interactions</a>
    <li><a href="#ref-for-propdef-min-width①">3.1. 
Sizing Properties</a>
    <li><a href="#ref-for-propdef-min-width②">3.1.2. 
Minimum Size Properties: the min-width and min-height properties</a> <a href="#ref-for-propdef-min-width③">(2)</a>
    <li><a href="#ref-for-propdef-min-width④">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-propdef-min-width⑤">4.1. 
Intrinsic Sizes</a> <a href="#ref-for-propdef-min-width⑥">(2)</a>
    <li><a href="#ref-for-propdef-min-width⑦"> Changes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-min-height">
   <b><a href="#propdef-min-height">#propdef-min-height</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-min-height">1.1. 
Module interactions</a>
    <li><a href="#ref-for-propdef-min-height①">3.1. 
Sizing Properties</a>
    <li><a href="#ref-for-propdef-min-height②">3.1.2. 
Minimum Size Properties: the min-width and min-height properties</a> <a href="#ref-for-propdef-min-height③">(2)</a>
    <li><a href="#ref-for-propdef-min-height④">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-propdef-min-height⑤">4.1. 
Intrinsic Sizes</a> <a href="#ref-for-propdef-min-height⑥">(2)</a>
    <li><a href="#ref-for-propdef-min-height⑦">5.1. 
	Percentage Sizing</a> <a href="#ref-for-propdef-min-height⑧">(2)</a> <a href="#ref-for-propdef-min-height⑨">(3)</a>
    <li><a href="#ref-for-propdef-min-height①⓪"> Changes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="min-width">
   <b><a href="#min-width">#min-width</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-min-width">3.3. 
Box Edges for Sizing: the box-sizing property</a>
    <li><a href="#ref-for-min-width①">4.1. 
Intrinsic Sizes</a> <a href="#ref-for-min-width②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="min-height">
   <b><a href="#min-height">#min-height</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-min-height">3.3. 
Box Edges for Sizing: the box-sizing property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="max-size-properties">
   <b><a href="#max-size-properties">#max-size-properties</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-max-size-properties">5.1. 
	Percentage Sizing</a> <a href="#ref-for-max-size-properties①">(2)</a> <a href="#ref-for-max-size-properties②">(3)</a> <a href="#ref-for-max-size-properties③">(4)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-max-width">
   <b><a href="#propdef-max-width">#propdef-max-width</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-max-width">1.1. 
Module interactions</a>
    <li><a href="#ref-for-propdef-max-width①">3.1. 
Sizing Properties</a>
    <li><a href="#ref-for-propdef-max-width②">3.1.3. 
Maximum Size Properties: the max-width and max-height properties</a> <a href="#ref-for-propdef-max-width③">(2)</a>
    <li><a href="#ref-for-propdef-max-width④">5.1. 
	Percentage Sizing</a> <a href="#ref-for-propdef-max-width⑤">(2)</a> <a href="#ref-for-propdef-max-width⑥">(3)</a>
    <li><a href="#ref-for-propdef-max-width⑦"> Compressible Replaced Elements</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-max-height">
   <b><a href="#propdef-max-height">#propdef-max-height</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-max-height">1.1. 
Module interactions</a>
    <li><a href="#ref-for-propdef-max-height①">3.1. 
Sizing Properties</a>
    <li><a href="#ref-for-propdef-max-height②">3.1.3. 
Maximum Size Properties: the max-width and max-height properties</a> <a href="#ref-for-propdef-max-height③">(2)</a>
    <li><a href="#ref-for-propdef-max-height④">5.1. 
	Percentage Sizing</a> <a href="#ref-for-propdef-max-height⑤">(2)</a>
    <li><a href="#ref-for-propdef-max-height⑥"> Compressible Replaced Elements</a>
    <li><a href="#ref-for-propdef-max-height⑦"> Changes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="max-width">
   <b><a href="#max-width">#max-width</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-max-width">3.3. 
Box Edges for Sizing: the box-sizing property</a>
    <li><a href="#ref-for-max-width①">4.1. 
Intrinsic Sizes</a> <a href="#ref-for-max-width②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="max-height">
   <b><a href="#max-height">#max-height</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-max-height">3.3. 
Box Edges for Sizing: the box-sizing property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="valdef-width-auto">
   <b><a href="#valdef-width-auto">#valdef-width-auto</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-width-auto">2. 
Terminology</a>
    <li><a href="#ref-for-valdef-width-auto①">2.1. 
Auto Box Sizes</a>
    <li><a href="#ref-for-valdef-width-auto②">3.1.2. 
Minimum Size Properties: the min-width and min-height properties</a>
    <li><a href="#ref-for-valdef-width-auto③">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-valdef-width-auto④">3.2.1. 
“Behaving as auto”</a> <a href="#ref-for-valdef-width-auto⑤">(2)</a> <a href="#ref-for-valdef-width-auto⑥">(3)</a> <a href="#ref-for-valdef-width-auto⑦">(4)</a>
    <li><a href="#ref-for-valdef-width-auto⑧">3.3. 
Box Edges for Sizing: the box-sizing property</a>
    <li><a href="#ref-for-valdef-width-auto⑨">4.1. 
Intrinsic Sizes</a> <a href="#ref-for-valdef-width-auto①⓪">(2)</a> <a href="#ref-for-valdef-width-auto①①">(3)</a> <a href="#ref-for-valdef-width-auto①②">(4)</a>
    <li><a href="#ref-for-valdef-width-auto①③">4.2. 
Intrinsic Contributions</a>
    <li><a href="#ref-for-valdef-width-auto①④">5.1. 
	Percentage Sizing</a> <a href="#ref-for-valdef-width-auto①⑤">(2)</a> <a href="#ref-for-valdef-width-auto①⑥">(3)</a>
    <li><a href="#ref-for-valdef-width-auto①⑦"> Changes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="automatic-size">
   <b><a href="#automatic-size">#automatic-size</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-automatic-size">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a> <a href="#ref-for-automatic-size①">(2)</a>
    <li><a href="#ref-for-automatic-size②">3.2.1. 
“Behaving as auto”</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="automatic-minimum-size">
   <b><a href="#automatic-minimum-size">#automatic-minimum-size</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-automatic-minimum-size">5.1. 
	Percentage Sizing</a> <a href="#ref-for-automatic-minimum-size①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="valdef-max-width-none">
   <b><a href="#valdef-max-width-none">#valdef-max-width-none</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-max-width-none">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="valdef-width-min-content">
   <b><a href="#valdef-width-min-content">#valdef-width-min-content</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-width-min-content">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a> <a href="#ref-for-valdef-width-min-content①">(2)</a> <a href="#ref-for-valdef-width-min-content②">(3)</a> <a href="#ref-for-valdef-width-min-content③">(4)</a>
    <li><a href="#ref-for-valdef-width-min-content④">3.3. 
Box Edges for Sizing: the box-sizing property</a>
    <li><a href="#ref-for-valdef-width-min-content⑤">4.1. 
Intrinsic Sizes</a>
    <li><a href="#ref-for-valdef-width-min-content⑥">5.1. 
	Percentage Sizing</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="valdef-width-max-content">
   <b><a href="#valdef-width-max-content">#valdef-width-max-content</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-width-max-content">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a> <a href="#ref-for-valdef-width-max-content①">(2)</a> <a href="#ref-for-valdef-width-max-content②">(3)</a> <a href="#ref-for-valdef-width-max-content③">(4)</a>
    <li><a href="#ref-for-valdef-width-max-content④">4.1. 
Intrinsic Sizes</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="valdef-width-fit-content-length-percentage">
   <b><a href="#valdef-width-fit-content-length-percentage">#valdef-width-fit-content-length-percentage</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-width-fit-content-length-percentage">3.1.1. 
Preferred Size Properties: the width and height properties</a>
    <li><a href="#ref-for-valdef-width-fit-content-length-percentage①">3.1.2. 
Minimum Size Properties: the min-width and min-height properties</a>
    <li><a href="#ref-for-valdef-width-fit-content-length-percentage②">3.1.3. 
Maximum Size Properties: the max-width and max-height properties</a>
    <li><a href="#ref-for-valdef-width-fit-content-length-percentage③">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a> <a href="#ref-for-valdef-width-fit-content-length-percentage④">(2)</a> <a href="#ref-for-valdef-width-fit-content-length-percentage⑤">(3)</a>
    <li><a href="#ref-for-valdef-width-fit-content-length-percentage⑥">3.3. 
Box Edges for Sizing: the box-sizing property</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="behave-as-auto">
   <b><a href="#behave-as-auto">#behave-as-auto</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-behave-as-auto">3.2.1. 
“Behaving as auto”</a>
    <li><a href="#ref-for-behave-as-auto①">4.1. 
Intrinsic Sizes</a> <a href="#ref-for-behave-as-auto②">(2)</a>
    <li><a href="#ref-for-behave-as-auto③">5.1. 
	Percentage Sizing</a> <a href="#ref-for-behave-as-auto④">(2)</a> <a href="#ref-for-behave-as-auto⑤">(3)</a> <a href="#ref-for-behave-as-auto⑥">(4)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="propdef-box-sizing">
   <b><a href="#propdef-box-sizing">#propdef-box-sizing</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-propdef-box-sizing">1.1. 
Module interactions</a>
    <li><a href="#ref-for-propdef-box-sizing①">3.2. 
Sizing Values: the &lt;length-percentage>, auto | none, min-content, max-content, and fit-content() values</a>
    <li><a href="#ref-for-propdef-box-sizing②">3.3. 
Box Edges for Sizing: the box-sizing property</a> <a href="#ref-for-propdef-box-sizing③">(2)</a> <a href="#ref-for-propdef-box-sizing④">(3)</a> <a href="#ref-for-propdef-box-sizing⑤">(4)</a> <a href="#ref-for-propdef-box-sizing⑥">(5)</a>
    <li><a href="#ref-for-propdef-box-sizing⑦"> Changes</a> <a href="#ref-for-propdef-box-sizing⑧">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="valdef-box-sizing-border-box">
   <b><a href="#valdef-box-sizing-border-box">#valdef-box-sizing-border-box</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-box-sizing-border-box">3.3. 
Box Edges for Sizing: the box-sizing property</a> <a href="#ref-for-valdef-box-sizing-border-box①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="valdef-column-width-min-content">
   <b><a href="#valdef-column-width-min-content">#valdef-column-width-min-content</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-column-width-min-content">3.4. 
New Column Sizing Values: the min-content, max-content, and fit-content() values</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="valdef-column-width-max-content">
   <b><a href="#valdef-column-width-max-content">#valdef-column-width-max-content</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-column-width-max-content">3.4. 
New Column Sizing Values: the min-content, max-content, and fit-content() values</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="valdef-column-width-fit-content-length-percentage">
   <b><a href="#valdef-column-width-fit-content-length-percentage">#valdef-column-width-fit-content-length-percentage</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-valdef-column-width-fit-content-length-percentage">3.4. 
New Column Sizing Values: the min-content, max-content, and fit-content() values</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="cyclic-percentage">
   <b><a href="#cyclic-percentage">#cyclic-percentage</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-cyclic-percentage">5.1. 
	Percentage Sizing</a> <a href="#ref-for-cyclic-percentage①">(2)</a> <a href="#ref-for-cyclic-percentage②">(3)</a> <a href="#ref-for-cyclic-percentage③">(4)</a>
    <li><a href="#ref-for-cyclic-percentage④"> Changes</a>
   </ul>
  </aside>
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